485BPOS

File No. 333-34844

811-09903

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933[X]

Pre-Effective Amendment No.[__]

Post-Effective Amendment No. 67[X]

and/or

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940[X]

Amendment No. 69[X]

(Check appropriate box or boxes.)

BNY MELLON FUNDS TRUST

(Exact Name of Registrant as Specified in Charter)

c/o The Dreyfus Corporation

200 Park Avenue, New York, New York 10166

(Address of Principal Executive Offices) (Zip Code)

Registrant's Telephone Number, including Area Code: (212) 922-6400

Bennett A. MacDougall, Esq.

200 Park Avenue

New York, New York 10166

(Name and Address of Agent for Service)

It is proposed that this filing will become effective (check appropriate box)

X__ immediately upon filing pursuant to paragraph (b)

_____on (date) pursuant to paragraph (b)

_____ (days) days after filing pursuant to paragraph (a)(1)

_____on (date) pursuant to paragraph (a)(1)

_____ (days) days after filing pursuant to paragraph (a)(2)

_____on (date) pursuant to paragraph (a)(2) of Rule 485

If appropriate, check the following box:

_____this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for effectiveness of this Amendment to the Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933 and has duly caused this Amendment to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, and State of New York on the 11^th day of January, 2018.

BNY MELLON FUNDS TRUST

BY:	/s/ Patrick T. Crowe*
	Patrick T. Crowe, PRESIDENT

Pursuant to the requirements of the Securities Act of 1933, this Amendment to the Registration Statement has been signed below by the following persons in the capacities and on the date indicated.

Signatures	Title	Date
/s/ Patrick T. Crowe* Patrick T. Crowe	President (Principal Executive Officer)	January 11, 2018
/s/ James Windels* James Windels	Treasurer (Principal Financial and Accounting Officer)	January 11, 2018
/s/ Patrick J. O’Connor* Patrick J. O’Connor	Chairman of the Board of Trustees	January 11, 2018
/s/ John R. Alchin* John R. Alchin	Trustee	January 11, 2018
/s/ Ronald R. Davenport* Ronald R. Davenport	Trustee	January 11, 2018
/s/ John L. Diederich* John L. Diederich	Trustee	January 11, 2018
/s/ Kim D. Kelly* Kim D. Kelly	Trustee	January 11, 2018
/s/ Kevin C. Phelan* Kevin C. Phelan	Trustee	January 11, 2018
/s/ Patrick J. Purcell* Patrick J. Purcell	Trustee	January 11, 2018
/s/ Thomas F. Ryan, Jr.* Thomas F. Ryan, Jr.	Trustee	January 11, 2018
/s/ Maureen M. Young* Maureen M. Young	Trustee	January 11, 2018

^*BY: /s/ Joseph M. Chioffi
Joseph M. Chioffi
Attorney-in-Fact

INDEX OF EXHIBITS

Exhibits

EX-101.INS – Instance Document.

EX-101.SCH – Taxonomy.

EX-101.CAL – Calculation Linkbase.

EX-101.DEF – Definition Linkbase.

EX-101.LAB – Labels Linkbase.

EX-101.PRE – Presentation Linkbase.

XML

Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Aug. 31, 2017
Registrant Name	BNY MELLON FUNDS TRUST
Central Index Key	0001111565
Amendment Flag	false
Document Creation Date	Dec. 27, 2017
Document Effective Date	Dec. 29, 2017
Prospectus Date	Dec. 29, 2017
Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Class M Shares
Prospectus:
Trading Symbol	MPLCX
Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Investor Shares
Prospectus:
Trading Symbol	MILCX
Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Class M Shares
Prospectus:
Trading Symbol	MMOMX
Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Investor Shares
Prospectus:
Trading Symbol	MMOIX
Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Class M Shares
Prospectus:
Trading Symbol	MTSMX
Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Investor Shares
Prospectus:
Trading Symbol	MTSIX
Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Class M Shares
Prospectus:
Trading Symbol	MPISX
Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Investor Shares
Prospectus:
Trading Symbol	MIISX
Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Class M Shares
Prospectus:
Trading Symbol	MPMCX
Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Investor Shares
Prospectus:
Trading Symbol	MIMSX
Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Class M Shares
Prospectus:
Trading Symbol	MPSSX
Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Investor Shares
Prospectus:
Trading Symbol	MISCX
Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Class M Shares
Prospectus:
Trading Symbol	MFOMX
Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Investor Shares
Prospectus:
Trading Symbol	MFOIX
Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Class M Shares
Prospectus:
Trading Symbol	MMCMX
Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Investor Shares
Prospectus:
Trading Symbol	MMCIX
Class M, Investor Prospectus | BNY Mellon International Fund | Class M Shares
Prospectus:
Trading Symbol	MPITX
Class M, Investor Prospectus | BNY Mellon International Fund | Investor Shares
Prospectus:
Trading Symbol	MIINX
Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Class M Shares
Prospectus:
Trading Symbol	MEMKX
Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Investor Shares
Prospectus:
Trading Symbol	MIEGX
Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Class M
Prospectus:
Trading Symbol	MPPMX
Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Investor Shares
Prospectus:
Trading Symbol	MARIX
Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Class M
Prospectus:
Trading Symbol	MLIMX
Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Investor
Prospectus:
Trading Symbol	MLIIX
Class M, Investor Prospectus | BNY Mellon Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MPBFX
Class M, Investor Prospectus | BNY Mellon Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MIBDX
Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MPIBX
Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MIIDX
Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Class M Shares
Prospectus:
Trading Symbol	BYMMX
Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Investor Shares
Prospectus:
Trading Symbol	BYMIX
Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Class M Shares
Prospectus:
Trading Symbol	MPSUX
Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Investor Shares
Prospectus:
Trading Symbol	MISTX
Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MPNIX
Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MINMX
Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MPSTX
Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MINSX
Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MPPIX
Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MIPAX
Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Class M Shares
Prospectus:
Trading Symbol	MMBMX
Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MMBIX
Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Class M
Prospectus:
Trading Symbol	MNYMX
Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Investor Shares
Prospectus:
Trading Symbol	MNYIX
Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Class M
Prospectus:
Trading Symbol	MOTMX
Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Investor
Prospectus:
Trading Symbol	MOTIX
Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Class M Shares
Prospectus:
Trading Symbol	MPBLX
Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Investor Shares
Prospectus:
Trading Symbol	MIBLX
Class M, Investor Prospectus | BNY Mellon Government Money Market Fund | Class M Shares
Prospectus:
Trading Symbol	MLMXX
Class M, Investor Prospectus | BNY Mellon Government Money Market Fund | Investor Shares
Prospectus:
Trading Symbol	MLOXX
Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund | Class M Shares
Prospectus:
Trading Symbol	MOMXX
Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares
Prospectus:
Trading Symbol	MNTXX
Investor Shares Prospectus | BNY Mellon Government Money Market Fund | Investor Shares
Prospectus:
Trading Symbol	MLOXX
Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares
Prospectus:
Trading Symbol	MNTXX
Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class A
Prospectus:
Trading Symbol	BMIAX
Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class C
Prospectus:
Trading Symbol	BMISX
Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class I
Prospectus:
Trading Symbol	BMIIX
Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class Y
Prospectus:
Trading Symbol	BMIYX

XML

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund

Fund Summary - BNY Mellon Large Cap Stock Fund

Investment Objective

The fund seeks capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Large Cap Stock Fund	Class M Shares	Investor Shares
Investment advisory fees	0.65%	0.65%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.07%	0.07%
Total annual fund operating expenses	0.84%	1.09%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Large Cap Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	86	268	466	1,037
Investor Shares	111	347	601	1,329

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Large Cap Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	86	268	466	1,037
Investor Shares	111	347	601	1,329

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 46.36% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks of large capitalization companies with market capitalizations of $5 billion or more at the time of purchase. The fund's portfolio managers apply a systematic, quantitative investment approach designed to identify and exploit relative misvaluations primarily within large-cap stocks in the U.S. stock market. The portfolio managers use a proprietary valuation model that identifies and ranks stocks to construct the fund's portfolio. The portfolio managers construct the fund's portfolio through a systematic structured approach, focusing on stock selection as opposed to making proactive decisions as to industry or sector exposure. Within each sector and style subset, the fund overweights the most attractive stocks and underweights or zero weights the stocks that have been ranked least attractive. The fund typically will hold between 100 and 175 securities.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on October 21, 2013. Prior to that date, the investment adviser selected securities for the fund using a proprietary computer model, along with fundamental analysis, to identify and rank stocks within industries or sectors, based on several characteristics, including value, growth and financial profile. Different investment strategies may lead to different performance results. The fund's performance for the periods shown in the bar chart and table reflects the fund's prior investment strategy.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2009: 18.04%
Worst Quarter
Q4, 2008: -22.75%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 14.33%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Large Cap Stock Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	8.83%	13.36%	5.71%
Investor Shares	8.37%	13.08%	5.43%
After Taxes on Distributions | Class M Shares	7.46%	8.47%	3.07%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	6.07%	9.77%	4.16%
S&P 500 reflects no deduction for fees, expenses or taxes	11.94%	14.65%	6.94%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Large Cap Stock Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 46.36% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

46.36%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks of large capitalization companies with market capitalizations of $5 billion or more at the time of purchase. The fund's portfolio managers apply a systematic, quantitative investment approach designed to identify and exploit relative misvaluations primarily within large-cap stocks in the U.S. stock market. The portfolio managers use a proprietary valuation model that identifies and ranks stocks to construct the fund's portfolio. The portfolio managers construct the fund's portfolio through a systematic structured approach, focusing on stock selection as opposed to making proactive decisions as to industry or sector exposure. Within each sector and style subset, the fund overweights the most attractive stocks and underweights or zero weights the stocks that have been ranked least attractive. The fund typically will hold between 100 and 175 securities.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on October 21, 2013. Prior to that date, the investment adviser selected securities for the fund using a proprietary computer model, along with fundamental analysis, to identify and rank stocks within industries or sectors, based on several characteristics, including value, growth and financial profile. Different investment strategies may lead to different performance results. The fund's performance for the periods shown in the bar chart and table reflects the fund's prior investment strategy.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2009: 18.04%
Worst Quarter
Q4, 2008: -22.75%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 14.33%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

14.33%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

18.04%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(22.75%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | S&P 500 reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.94%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.65%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.94%

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.84%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 86

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

268

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

466

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,037

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

86

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

268

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

466

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,037

Annual Return 2007

rr_AnnualReturn2007

10.19%

Annual Return 2008

rr_AnnualReturn2008

(39.44%)

Annual Return 2009

rr_AnnualReturn2009

27.24%

Annual Return 2010

rr_AnnualReturn2010

17.13%

Annual Return 2011

rr_AnnualReturn2011

(6.37%)

Annual Return 2012

rr_AnnualReturn2012

17.69%

Annual Return 2013

rr_AnnualReturn2013

27.41%

Annual Return 2014

rr_AnnualReturn2014

15.39%

Annual Return 2015

rr_AnnualReturn2015

(0.61%)

Annual Return 2016

rr_AnnualReturn2016

8.83%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.83%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.36%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.71%

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.46%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

8.47%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.07%

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.07%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

9.77%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.16%

Class M, Investor Prospectus | BNY Mellon Large Cap Stock Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.09%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 111

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

347

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

601

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,329

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

111

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

347

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

601

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,329

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.37%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.08%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.43%

XML

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund

Fund Summary - BNY Mellon Large Cap Market Opportunities Fund

Investment Objective

The fund seeks long-term capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Large Cap Market Opportunities Fund		Class M Shares	Investor Shares
Investment advisory fees	[1]	0.42%	0.42%
Other Expenses - Shareholder services fees		none	0.25%
Other Expenses - Administration fees		0.06%	0.06%
Other Expenses - Other expenses of the fund		0.18%	0.18%
Acquired fund fees and expenses	[2]	0.37%	0.37%
Total annual fund operating expenses		1.03%	1.28%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Large Cap Market Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	105	328	569	1,259
Investor Shares	130	406	702	1,545

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Large Cap Market Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	105	328	569	1,259
Investor Shares	130	406	702	1,545

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 30.26% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large cap companies. The fund currently considers large cap companies to be those companies with total market capitalizations of $5 billion or more at the time of purchase. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser or its affiliates that invest primarily in equity securities issued by large cap companies. The fund is designed to provide exposure to various large cap equity portfolio managers and investment strategies and styles. The fund invests directly in securities or in other mutual funds advised by the fund's investment adviser or its affiliates, referred to as underlying funds, which in turn may invest directly in securities as described below.

The investment adviser determines the investment strategies, including whether to implement such strategy by investing directly in securities or through an underlying fund, and sets the target allocations. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Focused Equity Strategy	38%	0% to 50%
U.S. Large Cap Equity Strategy	10%	0% to 50%
Dynamic Large Cap Value Strategy	14%	0% to 50%
Large Cap Growth Strategy	0%	0% to 50%
U.S. Large Cap Growth Strategy	27%	0% to 50%
Income Stock Strategy	11%	0% to 50%
Appreciation Strategy	0%	0% to 50%
Large Cap Dividend Strategy	0%	0% to 50%

The investment adviser has the discretion to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund, and the target allocations and ranges when the investment adviser deems it appropriate.

The fund's investment adviser monitors the portfolio trading activity within the investment strategies to promote tax efficiency and avoid wash sale transactions (i.e., selling a security at a loss, and within 30 days before or after the sale acquiring the same security, causing the loss to be disallowed and the security's basis adjusted), and executes all purchases and sales of portfolio securities of the fund. The fund will seek to reduce the impact of federal and state income taxes on the fund's after-tax returns by generally selling first the highest cost securities to reduce the amount of any capital gain and preferring the sale of securities producing long-term capital gains to those producing short-term capital gains.

The portion of the fund's assets allocated to the Focused Equity Strategy normally is invested in approximately 25-30 companies that are considered by the portfolio manager to be positioned for long-term earnings growth. The investment process for the Focused Equity Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with a bottom-up, fundamental approach to analyze individual companies.

Walter Scott & Partners Limited (Walter Scott), an affiliate of the fund's investment adviser, is the fund's sub-investment adviser responsible for the portion of the fund's assets allocated to the U.S. Large Cap Equity Strategy. Through extensive fundamental research, Walter Scott seeks investment opportunities in companies with the financial, operational and strategic strengths to underpin the potential for sustainable growth.

The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap companies. The portfolio manager focuses on individual stock selection (a "bottom-up" approach), emphasizing three key factors: value, sound business fundamentals, and positive business momentum. The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy also may be invested in Dreyfus Strategic Value Fund, a mutual fund advised by The Dreyfus Corporation and co-managed by the same portfolio manager responsible for the fund's Dynamic Large Cap Value Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Large Cap Growth Strategy normally is invested primarily in equity securities of large cap companies that are considered by the portfolio manager to be growth companies. Fundamental financial analysis is used to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: expected earnings growth rate exceeds market and industry trends; potential for positive earnings surprise relative to market expectations; positive operational or financial catalysts; attractive valuation based on growth prospects; and strong financial condition.

The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap U.S. companies. This portion of the fund's portfolio is structured so that its sector weightings generally are similar to those of the Russell 1000^® Growth Index. The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy also may be invested in Dreyfus Research Growth Fund, Inc., a mutual fund advised by The Dreyfus Corporation and managed by the same portfolio managers responsible for the fund's U.S. Large Cap Growth Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Income Stock Strategy is invested in BNY Mellon Income Stock Fund, a mutual fund advised by the fund's investment adviser. The underlying fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The underlying fund's portfolio manager chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The underlying fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The underlying fund may invest in the stocks of companies of any size, although it focuses on large-cap companies.

The portion of the fund's assets allocated to the Appreciation Strategy is invested in Dreyfus Appreciation Fund, Inc., a mutual fund advised by The Dreyfus Corporation and sub-advised by Fayez Sarofim & Co. The underlying fund focuses on "blue chip" companies with total market capitalizations of more than $5 billion at the time of purchase, including multinational companies. In addition to direct investments, the underlying fund may invest in securities of foreign companies in the form of U.S. dollar-denominated American Depositary Receipts (ADRs). The underlying fund employs a "buy-and-hold" investment strategy.

The portion of the fund's assets allocated to the Large Cap Dividend Strategy normally is invested primarily in equity securities, focusing on dividend-paying stocks and other investments and investment techniques that provide income. The portfolio manager chooses securities through a disciplined investment process that combines fundamental analysis and risk management. The Large Cap Dividend Strategy emphasizes those securities with above market average yield, although the portfolio manager may purchase those securities with low or no dividend. This portion of the fund's assets may be invested in the stocks of companies of any size, although the strategy focuses on large cap companies.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·ADR risk. ADRs may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert ADRs into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related ADR. The fund may invest in ADRs through an unsponsored facility where the depositary issues the depositary receipts without an agreement with the company that issues the underlying securities. Holders of unsponsored ADRs generally bear all the costs of such facilities, and the depositary of an unsponsored facility frequently is under no obligation to distribute shareholder communications received from the issuer of the deposited security or to pass through voting rights to the holders of the ADRs with respect to the deposited securities. As a result, available information concerning the issuer may not be as current as for sponsored ADRs, and the prices of unsponsored ADRs may be more volatile than if such instruments were sponsored by the issuer.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q1, 2012: 13.80%
Worst Quarter
Q3, 2011: -17.62%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 15.17%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Large Cap Market Opportunities Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
Class M Shares	11.40%	13.07%	11.60%	Jul. 30, 2010
Investor Shares	10.47%	12.72%	11.38%	Jul. 30, 2010
After Taxes on Distributions | Class M Shares	8.21%	10.02%	9.22%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	9.13%	10.15%	9.12%
S&P 500 reflects no deduction for fees, expenses or taxes	11.94%	14.65%	14.09%	Jul. 30, 2010

[1] The fund has agreed to pay an investment advisory fee at the annual rate of 0.70% applied to that portion of its average daily net assets allocated to direct investments in securities, and at the annual rate of 0.15% applied to that portion of its average daily net assets allocated to any underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Large Cap Market Opportunities Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 30.26% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

30.26%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

"Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large cap companies. The fund currently considers large cap companies to be those companies with total market capitalizations of $5 billion or more at the time of purchase. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser or its affiliates that invest primarily in equity securities issued by large cap companies. The fund is designed to provide exposure to various large cap equity portfolio managers and investment strategies and styles. The fund invests directly in securities or in other mutual funds advised by the fund's investment adviser or its affiliates, referred to as underlying funds, which in turn may invest directly in securities as described below.

The investment adviser determines the investment strategies, including whether to implement such strategy by investing directly in securities or through an underlying fund, and sets the target allocations. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Focused Equity Strategy	38%	0% to 50%
U.S. Large Cap Equity Strategy	10%	0% to 50%
Dynamic Large Cap Value Strategy	14%	0% to 50%
Large Cap Growth Strategy	0%	0% to 50%
U.S. Large Cap Growth Strategy	27%	0% to 50%
Income Stock Strategy	11%	0% to 50%
Appreciation Strategy	0%	0% to 50%
Large Cap Dividend Strategy	0%	0% to 50%

The investment adviser has the discretion to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund, and the target allocations and ranges when the investment adviser deems it appropriate.

The fund's investment adviser monitors the portfolio trading activity within the investment strategies to promote tax efficiency and avoid wash sale transactions (i.e., selling a security at a loss, and within 30 days before or after the sale acquiring the same security, causing the loss to be disallowed and the security's basis adjusted), and executes all purchases and sales of portfolio securities of the fund. The fund will seek to reduce the impact of federal and state income taxes on the fund's after-tax returns by generally selling first the highest cost securities to reduce the amount of any capital gain and preferring the sale of securities producing long-term capital gains to those producing short-term capital gains.

The portion of the fund's assets allocated to the Focused Equity Strategy normally is invested in approximately 25-30 companies that are considered by the portfolio manager to be positioned for long-term earnings growth. The investment process for the Focused Equity Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with a bottom-up, fundamental approach to analyze individual companies.

Walter Scott & Partners Limited (Walter Scott), an affiliate of the fund's investment adviser, is the fund's sub-investment adviser responsible for the portion of the fund's assets allocated to the U.S. Large Cap Equity Strategy. Through extensive fundamental research, Walter Scott seeks investment opportunities in companies with the financial, operational and strategic strengths to underpin the potential for sustainable growth.

The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap companies. The portfolio manager focuses on individual stock selection (a "bottom-up" approach), emphasizing three key factors: value, sound business fundamentals, and positive business momentum. The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy also may be invested in Dreyfus Strategic Value Fund, a mutual fund advised by The Dreyfus Corporation and co-managed by the same portfolio manager responsible for the fund's Dynamic Large Cap Value Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Large Cap Growth Strategy normally is invested primarily in equity securities of large cap companies that are considered by the portfolio manager to be growth companies. Fundamental financial analysis is used to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: expected earnings growth rate exceeds market and industry trends; potential for positive earnings surprise relative to market expectations; positive operational or financial catalysts; attractive valuation based on growth prospects; and strong financial condition.

The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap U.S. companies. This portion of the fund's portfolio is structured so that its sector weightings generally are similar to those of the Russell 1000^® Growth Index. The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy also may be invested in Dreyfus Research Growth Fund, Inc., a mutual fund advised by The Dreyfus Corporation and managed by the same portfolio managers responsible for the fund's U.S. Large Cap Growth Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Income Stock Strategy is invested in BNY Mellon Income Stock Fund, a mutual fund advised by the fund's investment adviser. The underlying fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The underlying fund's portfolio manager chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The underlying fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The underlying fund may invest in the stocks of companies of any size, although it focuses on large-cap companies.

The portion of the fund's assets allocated to the Appreciation Strategy is invested in Dreyfus Appreciation Fund, Inc., a mutual fund advised by The Dreyfus Corporation and sub-advised by Fayez Sarofim & Co. The underlying fund focuses on "blue chip" companies with total market capitalizations of more than $5 billion at the time of purchase, including multinational companies. In addition to direct investments, the underlying fund may invest in securities of foreign companies in the form of U.S. dollar-denominated American Depositary Receipts (ADRs). The underlying fund employs a "buy-and-hold" investment strategy.

The portion of the fund's assets allocated to the Large Cap Dividend Strategy normally is invested primarily in equity securities, focusing on dividend-paying stocks and other investments and investment techniques that provide income. The portfolio manager chooses securities through a disciplined investment process that combines fundamental analysis and risk management. The Large Cap Dividend Strategy emphasizes those securities with above market average yield, although the portfolio manager may purchase those securities with low or no dividend. This portion of the fund's assets may be invested in the stocks of companies of any size, although the strategy focuses on large cap companies.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·ADR risk. ADRs may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert ADRs into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related ADR. The fund may invest in ADRs through an unsponsored facility where the depositary issues the depositary receipts without an agreement with the company that issues the underlying securities. Holders of unsponsored ADRs generally bear all the costs of such facilities, and the depositary of an unsponsored facility frequently is under no obligation to distribute shareholder communications received from the issuer of the deposited security or to pass through voting rights to the holders of the ADRs with respect to the deposited securities. As a result, available information concerning the issuer may not be as current as for sponsored ADRs, and the prices of unsponsored ADRs may be more volatile than if such instruments were sponsored by the issuer.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

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Best Quarter
Q1, 2012: 13.80%
Worst Quarter
Q3, 2011: -17.62%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 15.17%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

15.17%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

13.80%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.62%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | S&P 500 reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.94%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.65%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

14.09%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.42%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.06%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.18%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.37%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.03%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 105

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

328

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

569

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,259

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

105

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

328

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

569

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,259

Annual Return 2011

rr_AnnualReturn2011

(4.27%)

Annual Return 2012

rr_AnnualReturn2012

14.37%

Annual Return 2013

rr_AnnualReturn2013

32.20%

Annual Return 2014

rr_AnnualReturn2014

8.90%

Annual Return 2015

rr_AnnualReturn2015

0.74%

Annual Return 2016

rr_AnnualReturn2016

11.40%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.40%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.07%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

11.60%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.21%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

10.02%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

9.22%

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

9.13%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

10.15%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

9.12%

Class M, Investor Prospectus | BNY Mellon Large Cap Market Opportunities Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.42%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.06%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.18%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.37%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.28%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 130

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

406

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

702

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,545

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

130

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

406

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

702

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,545

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.47%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

12.72%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

11.38%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

[1] The fund has agreed to pay an investment advisory fee at the annual rate of 0.70% applied to that portion of its average daily net assets allocated to direct investments in securities, and at the annual rate of 0.15% applied to that portion of its average daily net assets allocated to any underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund

Fund Summary - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund

Investment Objective

The fund seeks long-term capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund		Class M Shares	Investor Shares
Investment advisory fees	[1]	0.52%	0.52%
Other Expenses - Shareholder services fees		none	0.25%
Other Expenses - Administration fees		0.08%	0.08%
Other Expenses - Other expenses of the fund		0.05%	0.05%
Acquired fund fees and expenses	[2]	0.24%	0.24%
Total annual fund operating expenses		0.89%	1.14%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	91	284	493	1,096
Investor Shares	116	362	628	1,386

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	91	284	493	1,096
Investor Shares	116	362	628	1,386

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 24.05% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large cap companies. The fund currently considers large cap companies to be those companies with total market capitalizations of $5 billion or more at the time of purchase. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser or its affiliates that invest primarily in equity securities issued by large cap companies. The fund is designed to provide exposure to various large cap equity portfolio managers and investment strategies and styles and uses tax-sensitive strategies to reduce the impact of federal and state income taxes on the fund's after tax returns. The fund invests directly in securities or in other mutual funds advised by the fund's investment adviser or its affiliates, referred to as underlying funds, which in turn may invest directly in securities as described below.

The investment adviser determines the investment strategies, including whether to implement such strategy by investing directly in securities or through an underlying fund, and sets the target allocations. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Large Cap Tax-Sensitive Strategy	40%	20% to 60%
Large Cap Core Strategy	0%	0% to 30%
Focused Equity Strategy	20%	0% to 30%
U.S. Large Cap Equity Strategy	5%	0% to 30%
Dynamic Large Cap Value Strategy	9%	0% to 30%
Large Cap Growth Strategy	0%	0% to 30%
U.S. Large Cap Growth Strategy	19%	0% to 30%
Income Stock Strategy	7%	0% to 30%
Appreciation Strategy	0%	0% to 30%
Large Cap Dividend Strategy	0%	0% to 30%

The investment adviser has the discretion to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund, and the target allocations and ranges when the investment adviser deems it appropriate.

The fund's investment adviser monitors the portfolio trading activity within the investment strategies to promote tax efficiency and avoid wash sale transactions, and executes all purchases and sales of portfolio securities of the fund. The fund will seek to reduce the impact of federal and state income taxes on the fund's after-tax returns by using certain tax-sensitive strategies, which include for the fund as a whole generally selling first the highest cost securities to reduce the amount of any capital gain and preferring the sale of securities producing long-term capital gains to those producing short-term capital gains. Although the fund uses certain tax-sensitive strategies, the fund does not have any limitations regarding portfolio turnover and the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

The portion of the fund's assets allocated to the Large Cap Tax-Sensitive Strategy normally is invested primarily in equity securities of large cap companies included in the S&P 500^® Index (S&P 500). In selecting securities for the Large Cap Tax-Sensitive Strategy, the portfolio manager uses an optimization program to establish portfolio characteristics and risk factors that the portfolio manager determines are desirable relative to the aggregate characteristics and risk factors of the securities in the S&P 500. The portfolio characteristics and risk factors could be considered to have more or less risk than the S&P 500. The Large Cap Tax-Sensitive Strategy does not seek to add value through active security selection, nor does it target index replication. The portfolio manager seeks to actively and opportunistically realize capital gains and/or losses within this strategy as determined to be appropriate to improve the tax-sensitivity of the portfolio's investment performance. The Large Cap Tax-Sensitive Strategy may realize losses to offset gains incurred as a result of more closely aligning the portfolio with the characteristics of the S&P 500, or to allow more flexibility for offsetting gains incurred through subsequent rebalancing of the portfolio. In addition, the portfolio manager monitors trading activity for the fund as a whole to avoid wash sale transactions (i.e., selling a security at a loss, and within 30 days before or after the sale acquiring the same security, causing the loss to be disallowed and the security's basis adjusted), and may seek to offset any realized capital gains of the fund's other investment strategies.

The portion of the fund's assets allocated to the Large Cap Core Strategy normally is invested primarily in equity securities of large, established companies that the portfolio manager believes have proven track records and the potential for superior relative earnings growth. The investment process for the Large Cap Core Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with bottom-up, fundamental research to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: earnings power unrecognized by the market; sustainable revenue and cash flow growth; positive operational and/or financial catalysts; attractive relative value versus history and peers; and strong or improving financial condition.

The portion of the fund's assets allocated to the Focused Equity Strategy normally is invested in approximately 25-30 companies that are considered by the portfolio manager to be positioned for long-term earnings growth. The investment process for the Focused Equity Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with a bottom-up, fundamental approach to analyze individual companies.

Walter Scott & Partners Limited (Walter Scott), an affiliate of the fund's investment adviser, is the fund's sub-investment adviser responsible for the portion of the fund's assets allocated to the U.S. Large Cap Equity Strategy. Through extensive fundamental research, Walter Scott seeks investment opportunities in companies with the financial, operational and strategic strengths to underpin the potential for sustainable growth.

The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap companies. The portfolio manager focuses on individual stock selection (a "bottom-up" approach), emphasizing three key factors: value, sound business fundamentals, and positive business momentum. The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy also may be invested in Dreyfus Strategic Value Fund, a mutual fund advised by The Dreyfus Corporation and co-managed by the same portfolio manager responsible for the fund's Dynamic Large Cap Value Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Large Cap Growth Strategy normally is invested primarily in equity securities of large cap companies that are considered by the portfolio manager to be growth companies. Fundamental financial analysis is used to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: expected earnings growth rate exceeds market and industry trends; potential for positive earnings surprise relative to market expectations; positive operational or financial catalysts; attractive valuation based on growth prospects; and strong financial condition.

The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap U.S. companies. This portion of the fund's portfolio is structured so that its sector weightings generally are similar to those of the Russell 1000^® Growth Index. The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy also may be invested in Dreyfus Research Growth Fund, Inc., a mutual fund advised by The Dreyfus Corporation and managed by the same portfolio managers responsible for the fund's U.S. Large Cap Growth Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.  

The portion of the fund's assets allocated to the Income Stock Strategy is invested in BNY Mellon Income Stock Fund, a mutual fund advised by the fund's investment adviser. The underlying fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The underlying fund's portfolio manager chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The underlying fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The underlying fund may invest in the stocks of companies of any size, although it focuses on large-cap companies.

The portion of the fund's assets allocated to the Appreciation Strategy is invested in Dreyfus Appreciation Fund, Inc., a mutual fund advised by The Dreyfus Corporation and sub-advised by Fayez Sarofim & Co. The underlying fund focuses on "blue chip" companies with total market capitalizations of more than $5 billion at the time of purchase, including multinational companies. In addition to direct investments, the underlying fund may invest in securities of foreign companies in the form of U.S. dollar-denominated American Depositary Receipts (ADRs). The underlying fund employs a "buy-and-hold" investment strategy.

The portion of the fund's assets allocated to the Large Cap Dividend Strategy normally is invested primarily in equity securities, focusing on dividend-paying stocks and other investments and investment techniques that provide income. The portfolio manager chooses securities through a disciplined investment process that combines fundamental analysis and risk management. The Large Cap Dividend Strategy emphasizes those securities with above market average yield, although the portfolio manager may purchase those securities with low or no dividend. This portion of the fund's assets may be invested in the stocks of companies of any size, although the strategy focuses on large cap companies.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·ADR risk. ADRs may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert ADRs into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related ADR. The fund may invest in ADRs through an unsponsored facility where the depositary issues the depositary receipts without an agreement with the company that issues the underlying securities. Holders of unsponsored ADRs generally bear all the costs of such facilities, and the depositary of an unsponsored facility frequently is under no obligation to distribute shareholder communications received from the issuer of the deposited security or to pass through voting rights to the holders of the ADRs with respect to the deposited securities. As a result, available information concerning the issuer may not be as current as for sponsored ADRs, and the prices of unsponsored ADRs may be more volatile than if such instruments were sponsored by the issuer.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q1, 2012: 13.40%
Worst Quarter
Q3, 2011: -16.57%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 14.13%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
Class M Shares	11.49%	13.24%	12.17%	Jul. 30, 2010
Investor Shares	11.21%	13.27%	12.00%	Jul. 30, 2010
After Taxes on Distributions | Class M Shares	9.91%	11.30%	10.64%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	7.84%	10.28%	9.60%
S&P 500 reflects no deduction for fees, expenses or taxes	11.94%	14.65%	14.09%	Jul. 30, 2010

[1] The fund has agreed to pay an investment advisory fee at the annual rate of 0.70% applied to that portion of its average daily net assets allocated to direct investments in securities, and at the annual rate of 0.15% applied to that portion of its average daily net assets allocated to any underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 24.05% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

24.05%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

"Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large cap companies. The fund currently considers large cap companies to be those companies with total market capitalizations of $5 billion or more at the time of purchase. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser or its affiliates that invest primarily in equity securities issued by large cap companies. The fund is designed to provide exposure to various large cap equity portfolio managers and investment strategies and styles and uses tax-sensitive strategies to reduce the impact of federal and state income taxes on the fund's after tax returns. The fund invests directly in securities or in other mutual funds advised by the fund's investment adviser or its affiliates, referred to as underlying funds, which in turn may invest directly in securities as described below.

The investment adviser determines the investment strategies, including whether to implement such strategy by investing directly in securities or through an underlying fund, and sets the target allocations. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Large Cap Tax-Sensitive Strategy	40%	20% to 60%
Large Cap Core Strategy	0%	0% to 30%
Focused Equity Strategy	20%	0% to 30%
U.S. Large Cap Equity Strategy	5%	0% to 30%
Dynamic Large Cap Value Strategy	9%	0% to 30%
Large Cap Growth Strategy	0%	0% to 30%
U.S. Large Cap Growth Strategy	19%	0% to 30%
Income Stock Strategy	7%	0% to 30%
Appreciation Strategy	0%	0% to 30%
Large Cap Dividend Strategy	0%	0% to 30%

The investment adviser has the discretion to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund, and the target allocations and ranges when the investment adviser deems it appropriate.

The fund's investment adviser monitors the portfolio trading activity within the investment strategies to promote tax efficiency and avoid wash sale transactions, and executes all purchases and sales of portfolio securities of the fund. The fund will seek to reduce the impact of federal and state income taxes on the fund's after-tax returns by using certain tax-sensitive strategies, which include for the fund as a whole generally selling first the highest cost securities to reduce the amount of any capital gain and preferring the sale of securities producing long-term capital gains to those producing short-term capital gains. Although the fund uses certain tax-sensitive strategies, the fund does not have any limitations regarding portfolio turnover and the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

The portion of the fund's assets allocated to the Large Cap Tax-Sensitive Strategy normally is invested primarily in equity securities of large cap companies included in the S&P 500^® Index (S&P 500). In selecting securities for the Large Cap Tax-Sensitive Strategy, the portfolio manager uses an optimization program to establish portfolio characteristics and risk factors that the portfolio manager determines are desirable relative to the aggregate characteristics and risk factors of the securities in the S&P 500. The portfolio characteristics and risk factors could be considered to have more or less risk than the S&P 500. The Large Cap Tax-Sensitive Strategy does not seek to add value through active security selection, nor does it target index replication. The portfolio manager seeks to actively and opportunistically realize capital gains and/or losses within this strategy as determined to be appropriate to improve the tax-sensitivity of the portfolio's investment performance. The Large Cap Tax-Sensitive Strategy may realize losses to offset gains incurred as a result of more closely aligning the portfolio with the characteristics of the S&P 500, or to allow more flexibility for offsetting gains incurred through subsequent rebalancing of the portfolio. In addition, the portfolio manager monitors trading activity for the fund as a whole to avoid wash sale transactions (i.e., selling a security at a loss, and within 30 days before or after the sale acquiring the same security, causing the loss to be disallowed and the security's basis adjusted), and may seek to offset any realized capital gains of the fund's other investment strategies.

The portion of the fund's assets allocated to the Large Cap Core Strategy normally is invested primarily in equity securities of large, established companies that the portfolio manager believes have proven track records and the potential for superior relative earnings growth. The investment process for the Large Cap Core Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with bottom-up, fundamental research to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: earnings power unrecognized by the market; sustainable revenue and cash flow growth; positive operational and/or financial catalysts; attractive relative value versus history and peers; and strong or improving financial condition.

The portion of the fund's assets allocated to the Focused Equity Strategy normally is invested in approximately 25-30 companies that are considered by the portfolio manager to be positioned for long-term earnings growth. The investment process for the Focused Equity Strategy combines a top-down assessment of broad economic, political and social trends and their implications for different market and industry sectors with a bottom-up, fundamental approach to analyze individual companies.

Walter Scott & Partners Limited (Walter Scott), an affiliate of the fund's investment adviser, is the fund's sub-investment adviser responsible for the portion of the fund's assets allocated to the U.S. Large Cap Equity Strategy. Through extensive fundamental research, Walter Scott seeks investment opportunities in companies with the financial, operational and strategic strengths to underpin the potential for sustainable growth.

The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap companies. The portfolio manager focuses on individual stock selection (a "bottom-up" approach), emphasizing three key factors: value, sound business fundamentals, and positive business momentum. The portion of the fund's assets allocated to the Dynamic Large Cap Value Strategy also may be invested in Dreyfus Strategic Value Fund, a mutual fund advised by The Dreyfus Corporation and co-managed by the same portfolio manager responsible for the fund's Dynamic Large Cap Value Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.

The portion of the fund's assets allocated to the Large Cap Growth Strategy normally is invested primarily in equity securities of large cap companies that are considered by the portfolio manager to be growth companies. Fundamental financial analysis is used to identify companies that the portfolio manager believes offer one or more of the following characteristics, among others: expected earnings growth rate exceeds market and industry trends; potential for positive earnings surprise relative to market expectations; positive operational or financial catalysts; attractive valuation based on growth prospects; and strong financial condition.

The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy normally is invested primarily in equity securities of companies of any market capitalization, although the strategy focuses on large cap U.S. companies. This portion of the fund's portfolio is structured so that its sector weightings generally are similar to those of the Russell 1000^® Growth Index. The portion of the fund's assets allocated to the U.S. Large Cap Growth Strategy also may be invested in Dreyfus Research Growth Fund, Inc., a mutual fund advised by The Dreyfus Corporation and managed by the same portfolio managers responsible for the fund's U.S. Large Cap Growth Strategy using substantially similar investment strategies as those used in managing this portion of the fund's assets.  

The portion of the fund's assets allocated to the Income Stock Strategy is invested in BNY Mellon Income Stock Fund, a mutual fund advised by the fund's investment adviser. The underlying fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The underlying fund's portfolio manager chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The underlying fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The underlying fund may invest in the stocks of companies of any size, although it focuses on large-cap companies.

The portion of the fund's assets allocated to the Appreciation Strategy is invested in Dreyfus Appreciation Fund, Inc., a mutual fund advised by The Dreyfus Corporation and sub-advised by Fayez Sarofim & Co. The underlying fund focuses on "blue chip" companies with total market capitalizations of more than $5 billion at the time of purchase, including multinational companies. In addition to direct investments, the underlying fund may invest in securities of foreign companies in the form of U.S. dollar-denominated American Depositary Receipts (ADRs). The underlying fund employs a "buy-and-hold" investment strategy.

The portion of the fund's assets allocated to the Large Cap Dividend Strategy normally is invested primarily in equity securities, focusing on dividend-paying stocks and other investments and investment techniques that provide income. The portfolio manager chooses securities through a disciplined investment process that combines fundamental analysis and risk management. The Large Cap Dividend Strategy emphasizes those securities with above market average yield, although the portfolio manager may purchase those securities with low or no dividend. This portion of the fund's assets may be invested in the stocks of companies of any size, although the strategy focuses on large cap companies.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·ADR risk. ADRs may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert ADRs into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related ADR. The fund may invest in ADRs through an unsponsored facility where the depositary issues the depositary receipts without an agreement with the company that issues the underlying securities. Holders of unsponsored ADRs generally bear all the costs of such facilities, and the depositary of an unsponsored facility frequently is under no obligation to distribute shareholder communications received from the issuer of the deposited security or to pass through voting rights to the holders of the ADRs with respect to the deposited securities. As a result, available information concerning the issuer may not be as current as for sponsored ADRs, and the prices of unsponsored ADRs may be more volatile than if such instruments were sponsored by the issuer.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

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Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q1, 2012: 13.40%
Worst Quarter
Q3, 2011: -16.57%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 14.13%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

14.13%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

13.40%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(16.57%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | S&P 500 reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.94%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.65%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

14.09%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.52%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.08%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.24%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

0.89%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 91

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

284

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

493

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,096

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

91

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

284

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

493

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,096

Annual Return 2011

rr_AnnualReturn2011

(2.92%)

Annual Return 2012

rr_AnnualReturn2012

14.56%

Annual Return 2013

rr_AnnualReturn2013

30.90%

Annual Return 2014

rr_AnnualReturn2014

10.48%

Annual Return 2015

rr_AnnualReturn2015

0.82%

Annual Return 2016

rr_AnnualReturn2016

11.49%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.49%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.24%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

12.17%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

9.91%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.30%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

10.64%

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.84%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

10.28%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

9.60%

Class M, Investor Prospectus | BNY Mellon Tax Sensitive Large Cap Multi-Strategy Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.52%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.08%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.24%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.14%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 116

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

362

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

628

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,386

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

116

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

362

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

628

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,386

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.21%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.27%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

12.00%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 30, 2010

[1] The fund has agreed to pay an investment advisory fee at the annual rate of 0.70% applied to that portion of its average daily net assets allocated to direct investments in securities, and at the annual rate of 0.15% applied to that portion of its average daily net assets allocated to any underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Class M, Investor Prospectus | BNY Mellon Income Stock Fund

Fund Summary - BNY Mellon Income Stock Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Income Stock Fund	Class M Shares	Investor Shares
Investment advisory fees	0.65%	0.65%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.81%	1.06%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Income Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	83	259	450	1,002
Investor Shares	108	337	585	1,294

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Income Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	83	259	450	1,002
Investor Shares	108	337	585	1,294

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52.66% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks. The fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The investment adviser chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies. The fund's investment process is designed to provide investors with investment exposure to sector weightings and risk characteristics generally similar to those of the Dow Jones U.S. Select Dividend^™ Index (Dow Jones Index), but allocations may differ from those of the Dow Jones Index. The fund invests primarily in common stocks but also may invest up to 10% of its assets in convertible securities and up to 10% of its assets in preferred stocks.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Convertible securities risk. Convertible securities may be converted at either a stated price or stated rate into underlying shares of common stock. Convertible securities generally are subordinated to other similar but non-convertible securities of the same issuer. Although to a lesser extent than with fixed-income securities, the market value of convertible securities tends to decline as interest rates increase. In addition, because of the conversion feature, the market value of convertible securities tends to vary with fluctuations in the market value of the underlying common stock. Although convertible securities provide for a stable stream of income, they are subject to the risk that their issuers may default on their obligations.

·Preferred stock risk. Preferred stock is a class of a capital stock that typically pays dividends at a specified rate. Preferred stock is generally senior to common stock, but subordinate to debt securities, with respect to the payment of dividends and on liquidation of the issuer. The market value of preferred stock generally decreases when interest rates rise and is also affected by the issuer's ability to make payments on the preferred stock.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Dow Jones Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q2, 2009: 17.95%
Worst Quarter
Q4, 2008: -19.85%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 7.94%.

Average Annual Total Returns (as of 12/31/16)

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Income Stock Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	17.05%	14.98%	6.86%
Investor Shares	16.83%	14.68%	6.58%
After Taxes on Distributions | Class M Shares	15.52%	12.74%	5.17%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	10.80%	11.58%	5.23%
Dow Jones Index reflects no deduction for fees, expenses or taxes	21.98%	14.64%	6.72%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Income Stock Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Income Stock Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52.66% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

52.66%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks. The fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The investment adviser chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies. The fund's investment process is designed to provide investors with investment exposure to sector weightings and risk characteristics generally similar to those of the Dow Jones U.S. Select Dividend^™ Index (Dow Jones Index), but allocations may differ from those of the Dow Jones Index. The fund invests primarily in common stocks but also may invest up to 10% of its assets in convertible securities and up to 10% of its assets in preferred stocks.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Convertible securities risk. Convertible securities may be converted at either a stated price or stated rate into underlying shares of common stock. Convertible securities generally are subordinated to other similar but non-convertible securities of the same issuer. Although to a lesser extent than with fixed-income securities, the market value of convertible securities tends to decline as interest rates increase. In addition, because of the conversion feature, the market value of convertible securities tends to vary with fluctuations in the market value of the underlying common stock. Although convertible securities provide for a stable stream of income, they are subject to the risk that their issuers may default on their obligations.

·Preferred stock risk. Preferred stock is a class of a capital stock that typically pays dividends at a specified rate. Preferred stock is generally senior to common stock, but subordinate to debt securities, with respect to the payment of dividends and on liquidation of the issuer. The market value of preferred stock generally decreases when interest rates rise and is also affected by the issuer's ability to make payments on the preferred stock.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Dow Jones Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2009: 17.95%
Worst Quarter
Q4, 2008: -19.85%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 7.94%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

7.94%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.95%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.85%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns (as of 12/31/16)

Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Dow Jones Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

21.98%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.64%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.72%

Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.81%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 83

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

259

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

450

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,002

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

83

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

259

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

450

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,002

Annual Return 2007

rr_AnnualReturn2007

3.58%

Annual Return 2008

rr_AnnualReturn2008

(36.02%)

Annual Return 2009

rr_AnnualReturn2009

23.07%

Annual Return 2010

rr_AnnualReturn2010

14.27%

Annual Return 2011

rr_AnnualReturn2011

3.61%

Annual Return 2012

rr_AnnualReturn2012

14.86%

Annual Return 2013

rr_AnnualReturn2013

34.24%

Annual Return 2014

rr_AnnualReturn2014

10.64%

Annual Return 2015

rr_AnnualReturn2015

0.66%

Annual Return 2016

rr_AnnualReturn2016

17.05%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

17.05%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.98%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.86%

Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

15.52%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

12.74%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.17%

Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.80%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.58%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.23%

Class M, Investor Prospectus | BNY Mellon Income Stock Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.06%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 108

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

337

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

585

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,294

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

108

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

337

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

585

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,294

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

16.83%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.68%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.58%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Mid Cap Multi-Strategy Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 62.81% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

62.81%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of mid cap companies. The fund currently considers mid cap companies to be those companies with market capitalizations that are within the market capitalization range of companies comprising the Russell Midcap^® Index. As of November 30, 2017, the market capitalization of the largest company in the Russell Midcap^® Index was approximately $35.5 billion, and the weighted average and median market capitalizations of the Russell Midcap^® Index were approximately $14.9 billion and $7.9 billion, respectively. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser and sub-investment advisers that invest primarily in equity securities issued by mid cap companies. The fund is designed to provide exposure to various mid cap equity portfolio managers and investment strategies and styles. The fund may invest up to 15% of its assets in the equity securities of foreign issuers, including those in emerging market countries.

The investment adviser determines the investment strategies and sets the target allocations and ranges. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Mid Cap Tax-Sensitive Core Strategy	30%	0% to 50%
Opportunistic Mid Cap Value Strategy	17%	0% to 30%
Mid Cap Growth Strategy	20%	0% to 30%
Boston Partners Mid Cap Value Strategy	16%	0% to 30%
Geneva Mid Cap Growth Strategy	17%	0% to 30%

The Mid Cap Tax-Sensitive Core Strategy is employed by the fund's investment adviser, the Opportunistic Mid Cap Value Strategy and the Mid Cap Growth Strategy are employed by the fund's investment adviser using a proprietary investment process of The Boston Company Asset Management, LLC (TBCAM), an affiliate of the fund's investment adviser, and the Boston Partners Mid Cap Value Strategy and the Geneva Mid Cap Growth Strategy are employed by unaffiliated sub-investment advisers, namely, Boston Partners Global Investors, Inc. (Boston Partners), and Geneva Capital Management LLC (GCM), respectively.

The investment adviser has the discretion to change the investment strategies, including whether to implement a strategy employed by the fund's investment adviser or a sub-investment adviser, and the target allocations and ranges when the investment adviser deems it appropriate.

The portion of the fund's assets allocated to the Mid Cap Tax-Sensitive Core Strategy normally is invested primarily in equity securities of mid cap companies included in the Russell Midcap^® Index. In selecting securities for the Mid Cap Tax-Sensitive Core Strategy, the portfolio manager uses an optimization program to establish portfolio characteristics and risk factors that the portfolio manager determines are within an acceptable range of the Russell Midcap^® Index. The Mid Cap Tax-Sensitive Core Strategy does not seek to add value through active security selection, nor does it target index replication. The portfolio manager seeks to actively and opportunistically realize capital gains and/or losses within this strategy as determined to be appropriate to improve the tax-sensitivity of the portfolio's investment performance. The Mid Cap Tax-Sensitive Core Strategy may realize losses to offset gains incurred as a result of more closely aligning the portfolio with the characteristics of the Russell Midcap^® Index, or to allow more flexibility for offsetting gains incurred through subsequent rebalancing of the portfolio. In addition, the Mid Cap Tax-Sensitive Core Strategy may realize capital losses to offset any realized capital gains of the fund's other investment strategies.

The portion of the fund's assets allocated to the Opportunistic Mid Cap Value Strategy normally is invested primarily in equity securities of mid cap value companies. In constructing this portion of the fund's portfolio, the portfolio managers use an opportunistic value approach to identify stocks whose current market prices trade at a large discount to their intrinsic value, as calculated by the portfolio managers. The opportunistic value style attempts to benefit from valuation inefficiencies and underappreciated fundamental prospects present in the marketplace. For this portion of its portfolio, the fund generally seeks exposure to stocks and sectors that the portfolio managers perceive to be attractive from a valuation and fundamental standpoint.

The portion of the fund's assets allocated to the Mid Cap Growth Strategy normally is invested primarily in equity securities of mid cap companies with favorable growth prospects. In constructing this portion of the fund's portfolio, the portfolio managers use a "growth style" of investing, searching for companies whose fundamental strengths suggest the potential to provide superior earnings growth over time. The portfolio managers use a consistent, bottom-up approach which emphasizes individual stock selection. The portion of the fund's assets allocated to the Mid Cap Growth Strategy does not have any limitations regarding portfolio turnover, and may have portfolio turnover rates significantly in excess of 100%.

Boston Partners is the fund's sub-investment adviser responsible for the portion of the fund's assets allocated to the Boston Partners Mid Cap Value Strategy. The portion of the fund's assets allocated to the Boston Partners Mid Cap Value Strategy normally is invested in a diversified portfolio of mid cap stocks identified by Boston Partners as having value characteristics. Boston Partners employs a fundamental bottom-up, disciplined value investment process. Valuation, fundamentals and momentum are analyzed using a bottom-up blend of qualitative and quantitative inputs.

GCM is the fund's sub-investment adviser responsible for the portion of the fund’s assets allocated to the Geneva Mid Cap Growth Strategy. GCM seeks to identify high quality companies with low leverage, superior management, leadership positions within their industries, and a consistent, sustainable record of growth in managing its allocated portion of the fund's assets. In selecting stocks, GCM emphasizes bottom-up fundamental analysis to develop an understanding of a company supplemented by top-down considerations which include reviewing general economic and market trends and analyzing their effect on various industries. GCM also seeks to screen out high risk ideas, such as turnaround stories, initial public offerings and companies that are highly leveraged, non-U.S. based, or do not have earnings.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Midsize company risk. Midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Russell Midcap^® Index. The table also compares the average annual total returns of the fund's Class M shares and Investor shares to those of additional indices to show how the fund's performance compares with the returns of an index of mid-cap value stocks and an index of mid-cap growth stocks.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on August 20, 2012. Prior to that date, the fund generally had a single primary portfolio manager and investment strategy—selecting stocks of mid cap domestic companies through a disciplined investment process that combined computer modeling techniques, fundamental analysis and risk management. Different investment strategies may lead to different performance results. The fund's performance for periods prior to August 20, 2012 shown in the bar chart and table reflects the fund's investment strategy in effect prior to that date.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

	Best Quarter Q3, 2009: 17.89% Worst Quarter Q4, 2008: -24.86%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 12.63%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

12.63%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.89%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(24.86%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Russell Midcap® Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

13.80%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.72%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.86%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Russell Midcap® Value Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

20.00%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

15.70%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.59%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Russell Midcap® Growth Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.33%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.51%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.83%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.75%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.90%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 92

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

287

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

498

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,108

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

92

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

287

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

498

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,108

Annual Return 2007

rr_AnnualReturn2007

14.60%

Annual Return 2008

rr_AnnualReturn2008

(40.28%)

Annual Return 2009

rr_AnnualReturn2009

32.08%

Annual Return 2010

rr_AnnualReturn2010

28.44%

Annual Return 2011

rr_AnnualReturn2011

(8.85%)

Annual Return 2012

rr_AnnualReturn2012

13.16%

Annual Return 2013

rr_AnnualReturn2013

36.34%

Annual Return 2014

rr_AnnualReturn2014

10.10%

Annual Return 2015

rr_AnnualReturn2015

(2.69%)

Annual Return 2016

rr_AnnualReturn2016

11.62%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.62%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.03%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.92%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.18%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.62%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.87%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.95%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

10.17%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.46%

Class M, Investor Prospectus | BNY Mellon Mid Cap Multi-Strategy Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.75%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.15%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 117

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

365

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

633

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,398

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

117

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

365

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

633

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,398

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.33%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

12.75%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.65%

XML

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund

Fund Summary - BNY Mellon Small Cap Multi-Strategy Fund

Investment Objective

The fund seeks capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Small Cap Multi-Strategy Fund	Class M Shares	Investor Shares
Investment advisory fees	0.85%	0.85%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.06%	0.06%
Total annual fund operating expenses	1.03%	1.28%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Small Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	105	328	569	1,259
Investor Shares	130	406	702	1,545

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Small Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	105	328	569	1,259
Investor Shares	130	406	702	1,545

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 75.82% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small cap companies. The fund currently considers small cap companies to be those companies with market capitalizations that are equal to or less than the market capitalization of the largest company included in the Russell 2000^® Index. As of November 30, 2017, the market capitalization of the largest company in the Russell 2000^® Index was approximately $8.4 billion, and the weighted average and median market capitalizations of the Russell 2000^® Index were approximately $2.4 billion and $864 million, respectively. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser that invest primarily in equity securities issued by small cap companies. The fund is designed to provide exposure to various small cap equity portfolio managers and investment strategies and styles. The fund may invest up to 15% of its assets in the equity securities of foreign issuers, including up to 10% of its assets in the equity securities of issuers located in emerging market countries.

The investment adviser determines the investment strategies and sets the target allocations and ranges. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Opportunistic Small Cap Strategy	40%	0% to 50%
Small Cap Value Strategy	35%	0% to 40%
Small Cap Growth Strategy	25%	0% to 40%

The investment adviser has the discretion to change the investment strategies and the target allocations and ranges when the investment adviser deems it appropriate.

The portion of the fund's assets allocated to the Opportunistic Small Cap Strategy normally is invested primarily in equity securities of small cap companies. In constructing this portion of the fund's portfolio, the portfolio managers use a disciplined investment process that relies, in general, on proprietary fundamental research and valuation. Generally, elements of the process include analysis of mid-cycle business prospects, estimation of the intrinsic value of the company and the identification of a revaluation catalyst. The portfolio managers responsible for the Opportunistic Small Cap Strategy select securities that are believed to have attractive reward to risk opportunities and may actively adjust this portion of the fund's portfolio to reflect new developments.

The portion of the fund's assets allocated to the Small Cap Value Strategy normally is invested primarily in equity securities of small cap value companies. In constructing this portion of the fund's portfolio, the portfolio managers employ a value-based investment style, which means that they seek to identify those companies with stocks trading at prices below what are believed to be their intrinsic value. The portfolio managers responsible for the Small Cap Value Strategy focus primarily on individual stock selection instead of trying to predict which industries or sectors will perform best. The stock selection process is designed to produce a diversified portfolio of companies that the portfolio managers believe are undervalued relative to expected business growth, with the presence of a catalyst (such as a corporate restructuring, change in management or spin-off) that will trigger a near-term or mid-term price increase.

The portion of the fund's assets allocated to the Small Cap Growth Strategy normally is invested primarily in equity securities of small cap companies with favorable growth prospects. In constructing this portion of the fund's portfolio, the portfolio managers employ a growth-oriented investment style, which means the portfolio managers seek to identify those small cap companies which are experiencing or are expected to experience rapid earnings or revenue growth. The portfolio managers responsible for the Small Cap Growth Strategy look for high quality companies, especially those with products or services that are believed to be leaders in their market niches. The portfolio managers focus on individual stock selection instead of trying to predict which industries or sectors will perform best. The portion of the fund's assets allocated to the Small Cap Growth Strategy does not have any limitations regarding portfolio turnover, and may have portfolio turnover rates significantly in excess of 100%.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Russell 2000^® Index. The table also compares the average annual total returns of the fund's Class M shares and Investor shares to those of additional indices to show how the fund's performance compares with the returns of an index of small cap value stocks and an index of small cap growth stocks.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on August 20, 2012. Prior to that date, the fund generally had a single primary portfolio manager and investment strategy—selecting stocks of small-capitalization domestic companies through a disciplined investment process that combined computer modeling techniques, fundamental analysis and risk management. Different investment strategies may lead to different performance results. The fund's performance for periods prior to August 20, 2012 shown in the bar chart and table reflects the fund's investment strategy in effect prior to that date.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q4, 2010: 17.08%
Worst Quarter
Q3, 2011: -25.26%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 11.54%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Small Cap Multi-Strategy Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	18.91%	14.28%	5.90%
Investor Shares	18.62%	13.98%	5.69%
After Taxes on Distributions | Class M Shares	18.76%	13.78%	5.19%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	10.83%	11.43%	4.55%
Russell 2000® Index reflects no deduction for fees, expenses or taxes	21.31%	14.46%	7.07%
Russell 2000® Value Index reflects no deduction for fees, expenses or taxes	31.74%	15.07%	6.26%
Russell 2000® Growth Index reflects no deduction for fees, expenses or taxes	11.32%	13.74%	7.76%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Small Cap Multi-Strategy Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 75.82% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

75.82%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small cap companies. The fund currently considers small cap companies to be those companies with market capitalizations that are equal to or less than the market capitalization of the largest company included in the Russell 2000^® Index. As of November 30, 2017, the market capitalization of the largest company in the Russell 2000^® Index was approximately $8.4 billion, and the weighted average and median market capitalizations of the Russell 2000^® Index were approximately $2.4 billion and $864 million, respectively. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser that invest primarily in equity securities issued by small cap companies. The fund is designed to provide exposure to various small cap equity portfolio managers and investment strategies and styles. The fund may invest up to 15% of its assets in the equity securities of foreign issuers, including up to 10% of its assets in the equity securities of issuers located in emerging market countries.

The investment adviser determines the investment strategies and sets the target allocations and ranges. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Opportunistic Small Cap Strategy	40%	0% to 50%
Small Cap Value Strategy	35%	0% to 40%
Small Cap Growth Strategy	25%	0% to 40%

The investment adviser has the discretion to change the investment strategies and the target allocations and ranges when the investment adviser deems it appropriate.

The portion of the fund's assets allocated to the Opportunistic Small Cap Strategy normally is invested primarily in equity securities of small cap companies. In constructing this portion of the fund's portfolio, the portfolio managers use a disciplined investment process that relies, in general, on proprietary fundamental research and valuation. Generally, elements of the process include analysis of mid-cycle business prospects, estimation of the intrinsic value of the company and the identification of a revaluation catalyst. The portfolio managers responsible for the Opportunistic Small Cap Strategy select securities that are believed to have attractive reward to risk opportunities and may actively adjust this portion of the fund's portfolio to reflect new developments.

The portion of the fund's assets allocated to the Small Cap Value Strategy normally is invested primarily in equity securities of small cap value companies. In constructing this portion of the fund's portfolio, the portfolio managers employ a value-based investment style, which means that they seek to identify those companies with stocks trading at prices below what are believed to be their intrinsic value. The portfolio managers responsible for the Small Cap Value Strategy focus primarily on individual stock selection instead of trying to predict which industries or sectors will perform best. The stock selection process is designed to produce a diversified portfolio of companies that the portfolio managers believe are undervalued relative to expected business growth, with the presence of a catalyst (such as a corporate restructuring, change in management or spin-off) that will trigger a near-term or mid-term price increase.

The portion of the fund's assets allocated to the Small Cap Growth Strategy normally is invested primarily in equity securities of small cap companies with favorable growth prospects. In constructing this portion of the fund's portfolio, the portfolio managers employ a growth-oriented investment style, which means the portfolio managers seek to identify those small cap companies which are experiencing or are expected to experience rapid earnings or revenue growth. The portfolio managers responsible for the Small Cap Growth Strategy look for high quality companies, especially those with products or services that are believed to be leaders in their market niches. The portfolio managers focus on individual stock selection instead of trying to predict which industries or sectors will perform best. The portion of the fund's assets allocated to the Small Cap Growth Strategy does not have any limitations regarding portfolio turnover, and may have portfolio turnover rates significantly in excess of 100%.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Russell 2000^® Index. The table also compares the average annual total returns of the fund's Class M shares and Investor shares to those of additional indices to show how the fund's performance compares with the returns of an index of small cap value stocks and an index of small cap growth stocks.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on August 20, 2012. Prior to that date, the fund generally had a single primary portfolio manager and investment strategy—selecting stocks of small-capitalization domestic companies through a disciplined investment process that combined computer modeling techniques, fundamental analysis and risk management. Different investment strategies may lead to different performance results. The fund's performance for periods prior to August 20, 2012 shown in the bar chart and table reflects the fund's investment strategy in effect prior to that date.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q4, 2010: 17.08%
Worst Quarter
Q3, 2011: -25.26%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 11.54%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

11.54%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.08%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.26%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Russell 2000® Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

21.31%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.46%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.07%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Russell 2000® Value Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

31.74%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

15.07%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.26%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Russell 2000® Growth Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.32%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.74%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.76%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.06%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.03%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 105

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

328

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

569

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,259

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

105

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

328

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

569

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,259

Annual Return 2007

rr_AnnualReturn2007

6.33%

Annual Return 2008

rr_AnnualReturn2008

(35.46%)

Annual Return 2009

rr_AnnualReturn2009

16.62%

Annual Return 2010

rr_AnnualReturn2010

25.35%

Annual Return 2011

rr_AnnualReturn2011

(9.24%)

Annual Return 2012

rr_AnnualReturn2012

15.59%

Annual Return 2013

rr_AnnualReturn2013

44.13%

Annual Return 2014

rr_AnnualReturn2014

2.00%

Annual Return 2015

rr_AnnualReturn2015

(3.55%)

Annual Return 2016

rr_AnnualReturn2016

18.91%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

18.91%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.28%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.90%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

18.76%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.78%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.19%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.83%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.43%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.55%

Class M, Investor Prospectus | BNY Mellon Small Cap Multi-Strategy Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.06%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.28%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 130

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

406

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

702

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,545

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

130

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

406

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

702

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,545

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

18.62%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.98%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.69%

XML

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund

Fund Summary - BNY Mellon Focused Equity Opportunities Fund

Investment Objective

The fund seeks capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Focused Equity Opportunities Fund	Class M Shares	Investor Shares
Investment advisory fees	0.70%	0.70%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.05%	0.05%
Total annual fund operating expenses	0.87%	1.12%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Focused Equity Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	89	278	482	1,073
Investor Shares	114	356	617	1,363

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Focused Equity Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	89	278	482	1,073
Investor Shares	114	356	617	1,363

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 62.39% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund invests, under normal circumstances, in approximately 25-30 companies that are considered by the investment adviser to be positioned for long-term earnings growth. The fund may hold growth or value stocks or a blend of both. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies (generally, those companies with market capitalizations of $5 billion or more at the time of purchase). The fund invests primarily in equity securities of U.S. issuers, but may invest up to 25% of its assets in the equity securities of foreign issuers, including those in emerging market countries.

The portfolio manager monitors sector and security weightings and regularly evaluates the fund's risk-adjusted returns to manage the risk profile of the fund's portfolio. The portfolio manager adjusts exposure limits as necessary.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q1, 2012: 17.90%
Worst Quarter
Q3, 2011: -21.31%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 21.96%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Focused Equity Opportunities Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
Class M Shares	11.32%	14.74%	11.86%	Sep. 30, 2009
Investor Shares	11.00%	14.43%	11.58%	Sep. 30, 2009
After Taxes on Distributions | Class M Shares	8.86%	12.21%	10.13%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	8.14%	11.50%	9.42%
S&P 500 reflects no deduction for fees, expenses or taxes	11.94%	14.65%	13.27%	Sep. 30, 2009

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Focused Equity Opportunities Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 62.39% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

62.39%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund invests, under normal circumstances, in approximately 25-30 companies that are considered by the investment adviser to be positioned for long-term earnings growth. The fund may hold growth or value stocks or a blend of both. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies (generally, those companies with market capitalizations of $5 billion or more at the time of purchase). The fund invests primarily in equity securities of U.S. issuers, but may invest up to 25% of its assets in the equity securities of foreign issuers, including those in emerging market countries.

The portfolio manager monitors sector and security weightings and regularly evaluates the fund's risk-adjusted returns to manage the risk profile of the fund's portfolio. The portfolio manager adjusts exposure limits as necessary.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P 500^® Index (S&P 500).

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q1, 2012: 17.90%
Worst Quarter
Q3, 2011: -21.31%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 21.96%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

21.96%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.90%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.31%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | S&P 500 reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.94%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.65%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

13.27%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.70%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.87%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 89

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

278

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

482

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,073

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

89

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

278

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

482

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,073

Annual Return 2010

rr_AnnualReturn2010

15.72%

Annual Return 2011

rr_AnnualReturn2011

(9.59%)

Annual Return 2012

rr_AnnualReturn2012

18.04%

Annual Return 2013

rr_AnnualReturn2013

34.35%

Annual Return 2014

rr_AnnualReturn2014

11.55%

Annual Return 2015

rr_AnnualReturn2015

0.97%

Annual Return 2016

rr_AnnualReturn2016

11.32%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.32%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.74%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

11.86%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.86%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

12.21%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

10.13%

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.14%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.50%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

9.42%

Class M, Investor Prospectus | BNY Mellon Focused Equity Opportunities Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.70%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.12%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 114

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

356

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

617

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,363

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

114

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

356

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

617

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,363

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.00%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.43%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

11.58%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

XML

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund

Fund Summary - BNY Mellon Small/Mid Cap Multi-Strategy Fund

Investment Objective

The fund seeks capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Small/Mid Cap Multi-Strategy Fund	Class M Shares	Investor Shares
Investment advisory fees	0.75%	0.75%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.07%	0.07%
Total annual fund operating expenses	0.94%	1.19%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Small/Mid Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	96	300	520	1,155
Investor Shares	121	378	654	1,443

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Small/Mid Cap Multi-Strategy Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	96	300	520	1,155
Investor Shares	121	378	654	1,443

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 79.45% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small cap and mid cap companies. The fund currently considers small cap and mid cap companies to be those companies with market capitalizations that are within the market capitalization range of the smallest company included in the Russell 2000^® Index and the largest company included in the Russell Midcap^® Index. This corresponds to companies with market capitalizations as of November 30, 2017 of between approximately $21.6 million and $35.5 billion. As of November 30, 2017, the weighted average market capitalizations of the Russell 2000^® Index and the Russell Midcap^® Index were approximately $2.4 billion and $14.9 billion, respectively, and the median market capitalizations of the Russell 2000^® Index and the Russell Midcap^® Index were approximately $864 million and $7.9 billion, respectively. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser that invest primarily in equity securities issued by small cap and mid cap companies. The fund is designed to provide exposure to various small cap and mid cap equity portfolio managers and investment strategies and styles. The fund invests principally in common stocks. The fund may invest up to 15% of its assets in the equity securities of foreign issuers, including up to 10% of its assets in the equity securities of issuers located in emerging market countries.

The fund's investment adviser determines the investment strategies and sets the target allocations and ranges. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Opportunistic Small/Mid Cap Strategy	40%	0% to 50%
Small/Mid Cap Value Strategy	35%	0% to 40%
Small/Mid Cap Growth Strategy	25%	0% to 40%

The investment adviser has the discretion to change the investment strategies and the target allocations and ranges when the investment adviser deems it appropriate.

The portion of the fund's assets allocated to the Opportunistic Small/Mid Cap Strategy normally is invested primarily in equity securities of small cap and mid cap companies. In constructing this portion of the fund's portfolio, the portfolio managers use a disciplined investment process that relies, in general, on proprietary fundamental research and valuation. Generally, elements of the process include analysis of mid-cycle business prospects, estimation of the intrinsic value of the company and the identification of a revaluation catalyst. The portfolio managers responsible for the Opportunistic Small/Mid Cap Strategy select securities that are believed to have attractive reward to risk opportunities and may actively adjust this portion of the fund's portfolio to reflect new developments.

The portion of the fund's assets allocated to the Small/Mid Cap Value Strategy normally is invested primarily in equity securities of small cap and mid cap value companies. In constructing this portion of the fund's portfolio, the portfolio managers employ a value-based investment style, which means that they seek to identify those companies with stocks trading at prices below what are believed to be their intrinsic value. The portfolio managers responsible for the Small/Mid Cap Value Strategy focus primarily on individual stock selection instead of trying to predict which industries or sectors will perform best. The stock selection process is designed to produce a diversified portfolio of companies that the portfolio managers believe are undervalued relative to expected business growth, with the presence of a catalyst (such as a corporate restructuring, change in management or spin-off) that will trigger a near-term or mid-term price increase.

The portion of the fund's assets allocated to the Small/Mid Cap Growth Strategy normally is invested primarily in equity securities of small cap and mid cap companies with favorable growth prospects. In constructing this portion of the fund's portfolio, the portfolio managers employ a growth-oriented investment style, which means the portfolio managers seek to identify those small cap and mid cap companies which are experiencing or are expected to experience rapid earnings or revenue growth. The portfolio managers responsible for the Small/Mid Cap Growth Strategy look for high quality companies, especially those with products or services that are believed to be leaders in their market niches. The portfolio managers focus on individual stock selection instead of trying to predict which industries or sectors will perform best. The portion of the fund's assets allocated to the Small/Mid Cap Growth Strategy does not have any limitations regarding portfolio turnover, and may have portfolio turnover rates significantly in excess of 100%.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Russell 2500^™ Index. The table also compares the average annual total returns of the fund's Class M shares and Investor shares to those of additional indices to show how the fund's performance compares with the returns of an index of small to mid cap value stocks and an index of small to mid cap growth stocks.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on August 20, 2012 and April 28, 2014. From August 20, 2012 to April 28, 2014, the investment adviser selected securities for the fund using a disciplined investment process that combined quantitative modeling techniques, fundamental analysis and risk management. Prior to August 20, 2012, the investment adviser selected securities for the fund using proprietary computer models, along with fundamental analysis, to identify and rank stocks within industries or sectors, based on several characteristics, including value, growth and financial profile. Different investment strategies may lead to different performance results. The fund's performance for the periods from August 20, 2012 through April 27, 2014 and prior to August 20, 2012 shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q4, 2010: 18.37%
Worst Quarter
Q3, 2011: -24.85%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 12.53%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Small/Mid Cap Multi-Strategy Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception	Average Annual Returns, Inception Date
Class M Shares	17.07%	11.67%	11.29%	Sep. 30, 2009
Investor Shares	16.61%	11.34%	10.97%	Sep. 30, 2009
After Taxes on Distributions | Class M Shares	16.96%	9.18%	9.46%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	9.76%	8.73%	8.74%
Russell 2500™ Index reflects no deduction for fees, expenses or taxes	17.59%	14.54%	13.84%	Sep. 30, 2009
Russell 2500™ Value Index reflects no deduction for fees, expenses or taxes	25.20%	15.04%	13.74%	Sep. 30, 2009
Russell 2500™ Growth Index reflects no deduction for fees, expenses or taxes	9.73%	13.88%	13.87%	Sep. 30, 2009

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Small/Mid Cap Multi-Strategy Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 79.45% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

79.45%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small cap and mid cap companies. The fund currently considers small cap and mid cap companies to be those companies with market capitalizations that are within the market capitalization range of the smallest company included in the Russell 2000^® Index and the largest company included in the Russell Midcap^® Index. This corresponds to companies with market capitalizations as of November 30, 2017 of between approximately $21.6 million and $35.5 billion. As of November 30, 2017, the weighted average market capitalizations of the Russell 2000^® Index and the Russell Midcap^® Index were approximately $2.4 billion and $14.9 billion, respectively, and the median market capitalizations of the Russell 2000^® Index and the Russell Midcap^® Index were approximately $864 million and $7.9 billion, respectively. The fund normally allocates its assets among multiple investment strategies employed by the fund's investment adviser that invest primarily in equity securities issued by small cap and mid cap companies. The fund is designed to provide exposure to various small cap and mid cap equity portfolio managers and investment strategies and styles. The fund invests principally in common stocks. The fund may invest up to 15% of its assets in the equity securities of foreign issuers, including up to 10% of its assets in the equity securities of issuers located in emerging market countries.

The fund's investment adviser determines the investment strategies and sets the target allocations and ranges. The investment strategies and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the investment strategies as of the date of this prospectus were as follows:

Investment Strategy	Target	Range
Opportunistic Small/Mid Cap Strategy	40%	0% to 50%
Small/Mid Cap Value Strategy	35%	0% to 40%
Small/Mid Cap Growth Strategy	25%	0% to 40%

The investment adviser has the discretion to change the investment strategies and the target allocations and ranges when the investment adviser deems it appropriate.

The portion of the fund's assets allocated to the Opportunistic Small/Mid Cap Strategy normally is invested primarily in equity securities of small cap and mid cap companies. In constructing this portion of the fund's portfolio, the portfolio managers use a disciplined investment process that relies, in general, on proprietary fundamental research and valuation. Generally, elements of the process include analysis of mid-cycle business prospects, estimation of the intrinsic value of the company and the identification of a revaluation catalyst. The portfolio managers responsible for the Opportunistic Small/Mid Cap Strategy select securities that are believed to have attractive reward to risk opportunities and may actively adjust this portion of the fund's portfolio to reflect new developments.

The portion of the fund's assets allocated to the Small/Mid Cap Value Strategy normally is invested primarily in equity securities of small cap and mid cap value companies. In constructing this portion of the fund's portfolio, the portfolio managers employ a value-based investment style, which means that they seek to identify those companies with stocks trading at prices below what are believed to be their intrinsic value. The portfolio managers responsible for the Small/Mid Cap Value Strategy focus primarily on individual stock selection instead of trying to predict which industries or sectors will perform best. The stock selection process is designed to produce a diversified portfolio of companies that the portfolio managers believe are undervalued relative to expected business growth, with the presence of a catalyst (such as a corporate restructuring, change in management or spin-off) that will trigger a near-term or mid-term price increase.

The portion of the fund's assets allocated to the Small/Mid Cap Growth Strategy normally is invested primarily in equity securities of small cap and mid cap companies with favorable growth prospects. In constructing this portion of the fund's portfolio, the portfolio managers employ a growth-oriented investment style, which means the portfolio managers seek to identify those small cap and mid cap companies which are experiencing or are expected to experience rapid earnings or revenue growth. The portfolio managers responsible for the Small/Mid Cap Growth Strategy look for high quality companies, especially those with products or services that are believed to be leaders in their market niches. The portfolio managers focus on individual stock selection instead of trying to predict which industries or sectors will perform best. The portion of the fund's assets allocated to the Small/Mid Cap Growth Strategy does not have any limitations regarding portfolio turnover, and may have portfolio turnover rates significantly in excess of 100%.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among multiple investment strategies. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal or that an investment strategy will achieve its particular investment objective.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Russell 2500^™ Index. The table also compares the average annual total returns of the fund's Class M shares and Investor shares to those of additional indices to show how the fund's performance compares with the returns of an index of small to mid cap value stocks and an index of small to mid cap growth stocks.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on August 20, 2012 and April 28, 2014. From August 20, 2012 to April 28, 2014, the investment adviser selected securities for the fund using a disciplined investment process that combined quantitative modeling techniques, fundamental analysis and risk management. Prior to August 20, 2012, the investment adviser selected securities for the fund using proprietary computer models, along with fundamental analysis, to identify and rank stocks within industries or sectors, based on several characteristics, including value, growth and financial profile. Different investment strategies may lead to different performance results. The fund's performance for the periods from August 20, 2012 through April 27, 2014 and prior to August 20, 2012 shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q4, 2010: 18.37%
Worst Quarter
Q3, 2011: -24.85%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 12.53%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

12.53%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

18.37%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(24.85%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Russell 2500™ Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

17.59%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.54%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

13.84%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Russell 2500™ Value Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.20%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

15.04%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

13.74%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Russell 2500™ Growth Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

9.73%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.88%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

13.87%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.75%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.94%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 96

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

300

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

520

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,155

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

96

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

300

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

520

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,155

Annual Return 2010

rr_AnnualReturn2010

32.36%

Annual Return 2011

rr_AnnualReturn2011

(14.47%)

Annual Return 2012

rr_AnnualReturn2012

7.83%

Annual Return 2013

rr_AnnualReturn2013

31.60%

Annual Return 2014

rr_AnnualReturn2014

8.43%

Annual Return 2015

rr_AnnualReturn2015

(3.61%)

Annual Return 2016

rr_AnnualReturn2016

17.07%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

17.07%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.67%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

11.29%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

16.96%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

9.18%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

9.46%

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

9.76%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

8.73%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

8.74%

Class M, Investor Prospectus | BNY Mellon Small/Mid Cap Multi-Strategy Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.75%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.19%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 121

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

378

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

654

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,443

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

121

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

378

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

654

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,443

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

16.61%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.34%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

10.97%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2009

XML

Class M, Investor Prospectus | BNY Mellon International Fund

Fund Summary - BNY Mellon International Fund

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon International Fund	Class M Shares	Investor Shares
Investment advisory fees	0.85%	0.85%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.07%	0.07%
Total annual fund operating expenses	1.04%	1.29%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon International Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	106	331	574	1,271
Investor Shares	131	409	708	1,556

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon International Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	106	331	574	1,271
Investor Shares	131	409	708	1,556

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 81.88% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 65% of its total assets in equity securities of foreign issuers. Foreign issuers are companies organized under the laws of a foreign country, whose principal trading market is in a foreign country or with a majority of their assets or business outside the United States. The fund may invest in companies of any size. Though not specifically limited, the fund ordinarily will invest in a broad range of (and in any case at least five different) countries. The fund will limit its investments in any single company to no more than 5% of the fund's assets at the time of purchase.

The stocks purchased may have value and/or growth characteristics. The portfolio managers employ a bottom-up investment approach which emphasizes individual stock selection.

The stock selection process is designed to produce a diversified portfolio that, relative to the Morgan Stanley Capital International (MSCI) Europe, Australasia and Far East (EAFE) Index, has a below-average price/earnings ratio and an above-average earnings growth trend.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI EAFE Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on August 6, 2015. Prior to that date, the fund allocated its assets between a core investment style and a value investment style at the discretion of the investment adviser. Different investment strategies may lead to different performance results. The fund's performance shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q2, 2009: 23.73%
Worst Quarter
Q3, 2011: -21.38%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 23.04%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon International Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	(1.36%)	6.57%	(0.18%)
Investor Shares	(1.60%)	6.29%	(0.43%)
After Taxes on Distributions | Class M Shares	(1.65%)	6.31%	(0.66%)
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	(0.20%)	5.37%	0.23%
MSCI EAFE Index reflects no deduction for fees, expenses or taxes	1.00%	6.53%	0.75%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon International Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon International Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital growth.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 81.88% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

81.88%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 65% of its total assets in equity securities of foreign issuers. Foreign issuers are companies organized under the laws of a foreign country, whose principal trading market is in a foreign country or with a majority of their assets or business outside the United States. The fund may invest in companies of any size. Though not specifically limited, the fund ordinarily will invest in a broad range of (and in any case at least five different) countries. The fund will limit its investments in any single company to no more than 5% of the fund's assets at the time of purchase.

The stocks purchased may have value and/or growth characteristics. The portfolio managers employ a bottom-up investment approach which emphasizes individual stock selection.

The stock selection process is designed to produce a diversified portfolio that, relative to the Morgan Stanley Capital International (MSCI) Europe, Australasia and Far East (EAFE) Index, has a below-average price/earnings ratio and an above-average earnings growth trend.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI EAFE Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on August 6, 2015. Prior to that date, the fund allocated its assets between a core investment style and a value investment style at the discretion of the investment adviser. Different investment strategies may lead to different performance results. The fund's performance shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2009: 23.73%
Worst Quarter
Q3, 2011: -21.38%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 23.04%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

23.04%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

23.73%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.38%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon International Fund | MSCI EAFE Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.00%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.53%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.75%

Class M, Investor Prospectus | BNY Mellon International Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.04%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 106

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

331

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

574

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,271

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

106

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

331

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

574

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,271

Annual Return 2007

rr_AnnualReturn2007

4.33%

Annual Return 2008

rr_AnnualReturn2008

(40.67%)

Annual Return 2009

rr_AnnualReturn2009

29.02%

Annual Return 2010

rr_AnnualReturn2010

5.29%

Annual Return 2011

rr_AnnualReturn2011

(14.98%)

Annual Return 2012

rr_AnnualReturn2012

17.58%

Annual Return 2013

rr_AnnualReturn2013

26.47%

Annual Return 2014

rr_AnnualReturn2014

(7.27%)

Annual Return 2015

rr_AnnualReturn2015

1.05%

Annual Return 2016

rr_AnnualReturn2016

(1.36%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(1.36%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.57%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.18%)

Class M, Investor Prospectus | BNY Mellon International Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(1.65%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.31%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.66%)

Class M, Investor Prospectus | BNY Mellon International Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.20%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.37%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.23%

Class M, Investor Prospectus | BNY Mellon International Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.29%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 131

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

409

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

708

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,556

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

131

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

409

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

708

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,556

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(1.60%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.29%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.43%)

XML

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund

Fund Summary - BNY Mellon Emerging Markets Fund

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Emerging Markets Fund		Class M Shares	Investor Shares
Investment advisory fees		1.15%	1.15%
Other Expenses - Shareholder services fees		none	0.25%
Other Expenses - Administration fees		0.12%	0.12%
Other Expenses - Other expenses of the fund		0.13%	0.13%
Acquired fund fees and expenses	[1]	0.02%	0.02%
Total annual fund operating expenses		1.42%	1.67%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Emerging Markets Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	145	449	776	1,702
Investor Shares	170	526	907	1,976

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Emerging Markets Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	145	449	776	1,702
Investor Shares	170	526	907	1,976

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 91.81% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of companies organized, or with a majority of assets or operations, in countries considered to be emerging markets. Emerging market countries generally include all countries represented by the Morgan Stanley Capital International (MSCI) Emerging Markets Index. The fund may invest in companies of any size.

Normally, the fund will invest in a broad range of (and in any case at least five different) emerging market countries.

The stocks purchased may have value and/or growth characteristics. The portfolio managers employ a bottom-up investment approach which emphasizes individual stock selection.

The stock selection process is designed to produce a diversified portfolio that, relative to the MSCI Emerging Markets Index, has a below-average price/earnings ratio and an above-average earnings growth trend.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies, particularly the currencies of emerging market countries, are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI Emerging Markets Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on August 6, 2015. Prior to that date, the fund allocated its assets between a core investment style and a value investment style at the discretion of the investment adviser. Different investment strategies may lead to different performance results. The fund's performance shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

	Best Quarter Q2, 2009: 34.49% Worst Quarter Q4, 2008: -26.01%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 31.52%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Emerging Markets Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	10.62%	0.17%	0.73%
Investor Shares	10.33%	(0.09%)	0.49%
After Taxes on Distributions | Class M Shares	10.72%	0.24%	(0.38%)
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	6.51%	0.46%	1.09%
MSCI Emerging Markets Index reflects no deduction for fees, expenses or taxes	11.19%	1.28%	1.84%

[1] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Emerging Markets Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital growth.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 91.81% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

91.81%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

"Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of companies organized, or with a majority of assets or operations, in countries considered to be emerging markets. Emerging market countries generally include all countries represented by the Morgan Stanley Capital International (MSCI) Emerging Markets Index. The fund may invest in companies of any size.

Normally, the fund will invest in a broad range of (and in any case at least five different) emerging market countries.

The stocks purchased may have value and/or growth characteristics. The portfolio managers employ a bottom-up investment approach which emphasizes individual stock selection.

The stock selection process is designed to produce a diversified portfolio that, relative to the MSCI Emerging Markets Index, has a below-average price/earnings ratio and an above-average earnings growth trend.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies, particularly the currencies of emerging market countries, are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI Emerging Markets Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

The fund changed its investment strategy on August 6, 2015. Prior to that date, the fund allocated its assets between a core investment style and a value investment style at the discretion of the investment adviser. Different investment strategies may lead to different performance results. The fund's performance shown in the bar chart and table reflects the fund's investment strategy in effect during those periods.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

	Best Quarter Q2, 2009: 34.49% Worst Quarter Q4, 2008: -26.01%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 31.52%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

31.52%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

34.49%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.01%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | MSCI Emerging Markets Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

11.19%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.28%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.84%

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

1.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.13%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.02%

^[1]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.42%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 145

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

449

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

776

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,702

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

145

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

449

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

776

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,702

Annual Return 2007

rr_AnnualReturn2007

27.49%

Annual Return 2008

rr_AnnualReturn2008

(47.51%)

Annual Return 2009

rr_AnnualReturn2009

74.33%

Annual Return 2010

rr_AnnualReturn2010

16.72%

Annual Return 2011

rr_AnnualReturn2011

(21.66%)

Annual Return 2012

rr_AnnualReturn2012

16.95%

Annual Return 2013

rr_AnnualReturn2013

(1.98%)

Annual Return 2014

rr_AnnualReturn2014

(4.58%)

Annual Return 2015

rr_AnnualReturn2015

(16.64%)

Annual Return 2016

rr_AnnualReturn2016

10.62%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.62%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.17%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.73%

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.72%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.24%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.38%)

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.51%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.46%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.09%

Class M, Investor Prospectus | BNY Mellon Emerging Markets Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

1.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.13%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.02%

^[1]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.67%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 170

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

526

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

907

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,976

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

170

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

526

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

907

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,976

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.33%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.09%)

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.49%

[1] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

XML

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund

Fund Summary - BNY Mellon International Appreciation Fund

Investment Objective

The fund seeks to provide long-term capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon International Appreciation Fund	Class M	Investor Shares
Investment advisory fees	0.50%	0.50%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.30%	0.30%
Total annual fund operating expenses	0.92%	1.17%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon International Appreciation Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	94	293	509	1,131
Investor Shares	119	372	644	1,420

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon International Appreciation Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	94	293	509	1,131
Investor Shares	119	372	644	1,420

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 4.49% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund invests primarily in equity securities of non-U.S. issuers. The fund invests primarily in Depositary Receipts (DRs) representing the local shares of non-U.S. companies, in particular, American Depositary Receipts (ADRs). DRs are securities that represent ownership interests in the publicly-traded securities of non-U.S. issuers. ADRs are priced in U.S. dollars and traded in the United States on national securities exchanges or in the over-the-counter market. The fund pursues its objective by investing primarily in DRs representing securities of non-U.S. issuers, and generally will not invest in non-U.S. issuers that do not have sponsored or unsponsored DR programs even though such issuers may otherwise be an attractive investment for the fund.

In selecting securities, the investment adviser screens the Morgan Stanley Capital International (MSCI) Europe, Australasia and Far East (EAFE) Index universe of approximately 1,000 issuers for the availability of issuers with a sponsored or unsponsored DR facility. The investment adviser then analyzes issuers with DR facilities using a proprietary mathematical algorithm to reflect the characteristics of the developed markets. As a result of this process, the fund is expected to hold ADRs representing 200-300 foreign issuers. The fund's country allocation is expected to be within 5% of that of the MSCI EAFE Index, and, under normal circumstances, the fund will invest in at least 10 different countries.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards.

·Depositary receipts risk. Depositary receipts may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert depositary receipts into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related depositary receipt.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. Before the fund commenced operations (as of the close of business on September 12, 2008), substantially all of the assets of another investment company advised by an affiliate of the fund's investment adviser, BNY Hamilton International Equity Fund (the "predecessor fund"), a series of BNY Hamilton Funds, Inc., that, in all materials respects, had the same investment objective, strategies and policies as the fund, were transferred to the fund in a tax-free reorganization. The performance figures for the fund's Class M shares in the bar chart represent the performance of the predecessor fund's Institutional shares from year to year through September 12, 2008 and the performance of the fund's Class M shares thereafter. The average annual total returns for the fund's Class M shares and Investor shares in the table represent those of the predecessor fund's Institutional shares and Class A shares, respectively, through September 12, 2008 and the performance of the fund's Class M shares and Investor shares thereafter. These performance figures are compared to those of the MSCI EAFE Index. These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M*

*Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

Best Quarter
Q2, 2009: 25.00%
Worst Quarter
Q3, 2011: -21.21%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 19.43%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon International Appreciation Fund		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M	[1]	0.98%	6.13%	0.29%
Investor Shares	[2]	0.69%	5.85%	0.03%
After Taxes on Distributions | Class M		0.61%	5.75%	(0.09%)
After Taxes on Distributions and Sale of Fund Shares | Class M		1.36%	5.08%	0.45%
MSCI EAFE Index reflects no deduction for fees, expenses or taxes		1.00%	6.53%	0.75%

[1] Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

[2] Reflects the performance of the predecessor fund's Class A shares through September 12, 2008.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon International Appreciation Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to provide long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 4.49% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

4.49%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund invests primarily in equity securities of non-U.S. issuers. The fund invests primarily in Depositary Receipts (DRs) representing the local shares of non-U.S. companies, in particular, American Depositary Receipts (ADRs). DRs are securities that represent ownership interests in the publicly-traded securities of non-U.S. issuers. ADRs are priced in U.S. dollars and traded in the United States on national securities exchanges or in the over-the-counter market. The fund pursues its objective by investing primarily in DRs representing securities of non-U.S. issuers, and generally will not invest in non-U.S. issuers that do not have sponsored or unsponsored DR programs even though such issuers may otherwise be an attractive investment for the fund.

In selecting securities, the investment adviser screens the Morgan Stanley Capital International (MSCI) Europe, Australasia and Far East (EAFE) Index universe of approximately 1,000 issuers for the availability of issuers with a sponsored or unsponsored DR facility. The investment adviser then analyzes issuers with DR facilities using a proprietary mathematical algorithm to reflect the characteristics of the developed markets. As a result of this process, the fund is expected to hold ADRs representing 200-300 foreign issuers. The fund's country allocation is expected to be within 5% of that of the MSCI EAFE Index, and, under normal circumstances, the fund will invest in at least 10 different countries.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards.

·Depositary receipts risk. Depositary receipts may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert depositary receipts into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related depositary receipt.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. Before the fund commenced operations (as of the close of business on September 12, 2008), substantially all of the assets of another investment company advised by an affiliate of the fund's investment adviser, BNY Hamilton International Equity Fund (the "predecessor fund"), a series of BNY Hamilton Funds, Inc., that, in all materials respects, had the same investment objective, strategies and policies as the fund, were transferred to the fund in a tax-free reorganization. The performance figures for the fund's Class M shares in the bar chart represent the performance of the predecessor fund's Institutional shares from year to year through September 12, 2008 and the performance of the fund's Class M shares thereafter. The average annual total returns for the fund's Class M shares and Investor shares in the table represent those of the predecessor fund's Institutional shares and Class A shares, respectively, through September 12, 2008 and the performance of the fund's Class M shares and Investor shares thereafter. These performance figures are compared to those of the MSCI EAFE Index. These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M*

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower.

Bar Chart Footnotes [Text Block]

rr_BarChartFootnotesTextBlock

*Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2009: 25.00%
Worst Quarter
Q3, 2011: -21.21%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 19.43%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

19.43%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

25.00%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.21%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | MSCI EAFE Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.00%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.53%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.75%

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Class M

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.30%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.92%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 94

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

293

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

509

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,131

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

94

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

293

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

509

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,131

Annual Return 2007

rr_AnnualReturn2007

9.79%

Annual Return 2008

rr_AnnualReturn2008

(41.12%)

Annual Return 2009

rr_AnnualReturn2009

27.85%

Annual Return 2010

rr_AnnualReturn2010

6.76%

Annual Return 2011

rr_AnnualReturn2011

(13.41%)

Annual Return 2012

rr_AnnualReturn2012

18.70%

Annual Return 2013

rr_AnnualReturn2013

20.48%

Annual Return 2014

rr_AnnualReturn2014

(5.92%)

Annual Return 2015

rr_AnnualReturn2015

(0.88%)

Annual Return 2016

rr_AnnualReturn2016

0.98%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.98%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.13%

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.29%

^[1]

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Class M | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.61%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.75%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.09%)

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Class M | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.36%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.08%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.45%

Class M, Investor Prospectus | BNY Mellon International Appreciation Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.30%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.17%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 119

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

372

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

644

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,420

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

119

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

372

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

644

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,420

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.69%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.85%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.03%

^[2]

[1] Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

[2] Reflects the performance of the predecessor fund's Class A shares through September 12, 2008.

XML

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund

Fund Summary - BNY Mellon International Equity Income Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon International Equity Income Fund	Class M	Investor
Investment advisory fees	0.85%	0.85%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.12%	0.15%
Total annual fund operating expenses	1.09%	1.37%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon International Equity Income Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	111	347	601	1,329
Investor	139	434	750	1,646

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon International Equity Income Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	111	347	601	1,329
Investor	139	434	750	1,646

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 46.42% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund focuses on dividend-paying stocks of foreign companies, including those in emerging market countries. The fund normally invests substantially all of its assets in the equity securities of issuers located outside the United States and diversifies broadly among developed and emerging market countries. The fund may invest in the stocks of companies of any market capitalization.

The fund's portfolio managers select stocks through a disciplined investment process using proprietary quantitative computer models that analyze a diverse set of stock characteristics to identify and rank stocks based on earnings quality. Based on this analysis, the portfolio managers generally select from the higher ranked dividend-paying securities those stocks that they believe will continue to pay above-average dividends. The portfolio managers will seek to overweight higher dividend-paying stocks, while maintaining country and sector weights generally similar to those of the Morgan Stanley Capital International All Country World Ex-U.S.A. Index (MSCI ACWI Ex-USA), an unmanaged index that measures the equity market performance of developed and emerging market countries, excluding the United States.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies, particularly the currencies of emerging market countries, are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI ACWI Ex-USA Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2013: 8.99%
Worst Quarter
Q3, 2015: -11.17%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 21.25%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon International Equity Income Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class M	7.62%	3.18%	3.40%		Dec. 15, 2011
Investor	7.37%	2.92%	3.14%		Dec. 15, 2011
After Taxes on Distributions | Class M	7.22%	2.59%	2.81%
After Taxes on Distributions and Sale of Fund Shares | Class M	5.17%	2.79%	2.96%
MSCI ACWI Ex-USA Index reflects no deduction for fees, expenses or taxes	4.50%	5.00%	4.69%	[1]	Nov. 30, 2011

[1] For comparative purposes, the value of the MSCI ACWI Ex-USA Index on 11/30/11 is used as the beginning value on 12/15/11.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon International Equity Income Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 46.42% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

46.42%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities. The fund focuses on dividend-paying stocks of foreign companies, including those in emerging market countries. The fund normally invests substantially all of its assets in the equity securities of issuers located outside the United States and diversifies broadly among developed and emerging market countries. The fund may invest in the stocks of companies of any market capitalization.

The fund's portfolio managers select stocks through a disciplined investment process using proprietary quantitative computer models that analyze a diverse set of stock characteristics to identify and rank stocks based on earnings quality. Based on this analysis, the portfolio managers generally select from the higher ranked dividend-paying securities those stocks that they believe will continue to pay above-average dividends. The portfolio managers will seek to overweight higher dividend-paying stocks, while maintaining country and sector weights generally similar to those of the Morgan Stanley Capital International All Country World Ex-U.S.A. Index (MSCI ACWI Ex-USA), an unmanaged index that measures the equity market performance of developed and emerging market countries, excluding the United States.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies, particularly the currencies of emerging market countries, are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the MSCI ACWI Ex-USA Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2013: 8.99%
Worst Quarter
Q3, 2015: -11.17%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 21.25%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

21.25%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2013

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

8.99%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(11.17%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | MSCI ACWI Ex-USA Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

4.50%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.00%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.69%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2011

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Class M

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.12%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.09%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 111

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

347

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

601

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,329

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

111

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

347

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

601

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,329

Annual Return 2012

rr_AnnualReturn2012

15.93%

Annual Return 2013

rr_AnnualReturn2013

7.67%

Annual Return 2014

rr_AnnualReturn2014

(5.95%)

Annual Return 2015

rr_AnnualReturn2015

(7.44%)

Annual Return 2016

rr_AnnualReturn2016

7.62%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.62%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.18%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.40%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 15, 2011

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Class M | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.22%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.59%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.81%

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Class M | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

5.17%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.79%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.96%

Class M, Investor Prospectus | BNY Mellon International Equity Income Fund | Investor

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.85%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.15%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.37%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 139

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

434

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

750

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,646

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

139

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

434

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

750

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,646

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

7.37%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.92%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.14%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 15, 2011

[1] For comparative purposes, the value of the MSCI ACWI Ex-USA Index on 11/30/11 is used as the beginning value on 12/15/11.

XML

Class M, Investor Prospectus | BNY Mellon Bond Fund

Fund Summary - BNY Mellon Bond Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and current income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.40%	0.40%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.56%	0.81%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 72.85% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in bonds. The investment adviser actively manages the fund's bond market and maturity exposure and credit profile and uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The fund's investments in bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Investments in bonds may include government securities, corporate bonds, mortgage-related securities and municipal securities. Generally, the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual bonds of any duration. There are no restrictions on the dollar-weighted average maturity of the fund's portfolio or on the maturities of the individual bonds the fund may purchase. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Interest rate changes may have different effects on the values of mortgage-related securities because of prepayment and extension risks.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Mortgage-related securities risk. Mortgage-related securities are complex derivative instruments, subject to credit, prepayment and extension risk, and may be more volatile, less liquid and more difficult to price accurately than more traditional debt securities. The fund is subject to the credit risk associated with these securities, including the market's perception of the creditworthiness of the issuing federal agency, as well as the credit quality of the underlying assets. Although certain mortgage-related securities are guaranteed as to the timely payment of interest and principal by a third party (such as a U.S. government agency or instrumentality with respect to government-related mortgage-backed securities) the market prices for such securities are not guaranteed and will fluctuate. Declining interest rates may result in the prepayment of higher yielding underlying mortgages and the reinvestment of proceeds at lower interest rates can reduce the fund's potential price gain in response to falling interest rates, reduce the fund's yield and/or cause the fund's share price to fall (prepayment risk). Rising interest rates may result in a drop in prepayments of the underlying mortgages, which would increase the fund's sensitivity to rising interest rates and its potential for price declines (extension risk).

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Aggregate Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q4, 2008: 4.63%
Worst Quarter
Q2, 2013: -2.98%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.47%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Bond Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	2.53%	2.28%	4.21%
Investor Shares	2.34%	2.02%	3.95%
After Taxes on Distributions | Class M Shares	1.22%	0.96%	2.76%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	1.48%	1.23%	2.72%
Bloomberg Barclays U.S. Aggregate Bond Index reflects no deduction for fees, expenses or taxes	2.65%	2.23%	4.34%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and current income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 72.85% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

72.85%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in bonds. The investment adviser actively manages the fund's bond market and maturity exposure and credit profile and uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The fund's investments in bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Investments in bonds may include government securities, corporate bonds, mortgage-related securities and municipal securities. Generally, the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual bonds of any duration. There are no restrictions on the dollar-weighted average maturity of the fund's portfolio or on the maturities of the individual bonds the fund may purchase. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Interest rate changes may have different effects on the values of mortgage-related securities because of prepayment and extension risks.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Mortgage-related securities risk. Mortgage-related securities are complex derivative instruments, subject to credit, prepayment and extension risk, and may be more volatile, less liquid and more difficult to price accurately than more traditional debt securities. The fund is subject to the credit risk associated with these securities, including the market's perception of the creditworthiness of the issuing federal agency, as well as the credit quality of the underlying assets. Although certain mortgage-related securities are guaranteed as to the timely payment of interest and principal by a third party (such as a U.S. government agency or instrumentality with respect to government-related mortgage-backed securities) the market prices for such securities are not guaranteed and will fluctuate. Declining interest rates may result in the prepayment of higher yielding underlying mortgages and the reinvestment of proceeds at lower interest rates can reduce the fund's potential price gain in response to falling interest rates, reduce the fund's yield and/or cause the fund's share price to fall (prepayment risk). Rising interest rates may result in a drop in prepayments of the underlying mortgages, which would increase the fund's sensitivity to rising interest rates and its potential for price declines (extension risk).

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Aggregate Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q4, 2008: 4.63%
Worst Quarter
Q2, 2013: -2.98%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.47%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

3.47%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2008

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

4.63%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(2.98%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Bond Fund | Bloomberg Barclays U.S. Aggregate Bond Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.65%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.23%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.34%

Class M, Investor Prospectus | BNY Mellon Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.56%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 57

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

179

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

313

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

701

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

57

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

179

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

313

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 701

Annual Return 2007

rr_AnnualReturn2007

6.74%

Annual Return 2008

rr_AnnualReturn2008

6.05%

Annual Return 2009

rr_AnnualReturn2009

6.70%

Annual Return 2010

rr_AnnualReturn2010

5.89%

Annual Return 2011

rr_AnnualReturn2011

5.48%

Annual Return 2012

rr_AnnualReturn2012

6.04%

Annual Return 2013

rr_AnnualReturn2013

(2.29%)

Annual Return 2014

rr_AnnualReturn2014

4.63%

Annual Return 2015

rr_AnnualReturn2015

0.70%

Annual Return 2016

rr_AnnualReturn2016

2.53%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.53%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.28%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.21%

Class M, Investor Prospectus | BNY Mellon Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.22%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.96%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.76%

Class M, Investor Prospectus | BNY Mellon Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.48%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.23%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.72%

Class M, Investor Prospectus | BNY Mellon Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.81%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 83

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

259

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

450

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,002

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

83

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

259

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

450

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,002

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.34%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.02%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.95%

XML

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund

Fund Summary - BNY Mellon Intermediate Bond Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and current income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Intermediate Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.40%	0.40%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.56%	0.81%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Intermediate Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Intermediate Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 48.97% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in bonds. The investment adviser actively manages bond market and maturity exposure and credit profile and uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The fund's investments in bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Investments in bonds may include government securities, corporate bonds and municipal securities. Generally, the fund's average effective portfolio maturity will be between 3 and 10 years and the average effective duration of the fund's portfolio will be between 2.5 and 5.5 years. The fund may invest in individual bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity.

Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Intermediate Government/Credit Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q4, 2008: 4.40%
Worst Quarter
Q2, 2013: -2.25%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 2.09%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Intermediate Bond Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	2.01%	1.46%	3.47%
Investor Shares	1.82%	1.22%	3.22%
After Taxes on Distributions | Class M Shares	1.10%	0.53%	2.28%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	1.15%	0.73%	2.24%
Bloomberg Barclays U.S. Intermediate Government/Credit Index reflects no deduction for fees, expenses or taxes	2.08%	1.85%	3.84%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Intermediate Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and current income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 48.97% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

48.97%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in bonds. The investment adviser actively manages bond market and maturity exposure and credit profile and uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The fund's investments in bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Investments in bonds may include government securities, corporate bonds and municipal securities. Generally, the fund's average effective portfolio maturity will be between 3 and 10 years and the average effective duration of the fund's portfolio will be between 2.5 and 5.5 years. The fund may invest in individual bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity.

Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Intermediate Government/Credit Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q4, 2008: 4.40%
Worst Quarter
Q2, 2013: -2.25%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 2.09%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

2.09%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2008

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

4.40%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(2.25%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Bloomberg Barclays U.S. Intermediate Government/Credit Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.08%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.85%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.84%

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.56%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 57

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

179

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

313

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

701

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

57

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

179

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

313

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 701

Annual Return 2007

rr_AnnualReturn2007

7.16%

Annual Return 2008

rr_AnnualReturn2008

5.52%

Annual Return 2009

rr_AnnualReturn2009

6.16%

Annual Return 2010

rr_AnnualReturn2010

4.70%

Annual Return 2011

rr_AnnualReturn2011

4.11%

Annual Return 2012

rr_AnnualReturn2012

4.15%

Annual Return 2013

rr_AnnualReturn2013

(1.30%)

Annual Return 2014

rr_AnnualReturn2014

1.95%

Annual Return 2015

rr_AnnualReturn2015

0.58%

Annual Return 2016

rr_AnnualReturn2016

2.01%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.01%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.46%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.47%

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.10%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.53%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.28%

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.15%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.73%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.24%

Class M, Investor Prospectus | BNY Mellon Intermediate Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.81%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 83

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

259

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

450

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,002

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

83

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

259

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

450

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,002

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.82%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.22%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.22%

XML

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund

Fund Summary - BNY Mellon Corporate Bond Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and current income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Corporate Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.40%	0.40%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.56%	0.81%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Corporate Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Corporate Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	57	179	313	701
Investor Shares	83	259	450	1,002

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 33.05% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in corporate bonds. The investment adviser uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The investment adviser actively manages the fund's bond market and maturity exposure and credit profile. The fund normally invests at least 80% of its assets in bonds rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser, with at least 65% of such investment grade bonds issued by corporations or the U.S. government or its agencies. Generally, the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual bonds of any duration. There are no restrictions on the dollar-weighted average maturity of the fund's portfolio or on the maturities of the individual bonds the fund may purchase. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

In selecting corporate bonds for investment, the fund's portfolio manager analyzes fundamental metrics, including the issuer's cash flow, leverage and operating margins, as well as its business strategy and operating performance, and macro economic factors. The fund typically sells a security when the portfolio manager believes that there has been a negative change in the credit quality of the issuer or has identified a more attractive opportunity or when the portfolio manager seeks to manage the fund's duration or tax position or to provide liquidity to meet shareholder redemptions.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Intermediate Credit Index and the Bloomberg Barclays U.S. Credit Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q1, 2016: 3.28%
Worst Quarter
Q2, 2013: -2.81%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 5.04%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Corporate Bond Fund	Average Annual Returns, 1 Year	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class M Shares	6.43%	3.67%		Mar. 02, 2012
Investor Shares	6.08%	3.39%		Mar. 02, 2012
After Taxes on Distributions | Class M Shares	4.78%	2.26%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	3.63%	2.19%
Bloomberg Barclays U.S. Intermediate Credit Index reflects no deduction for fees, expenses or taxes	5.63%	3.38%	[1]	Feb. 29, 2012
Bloomberg Barclays U.S. Credit Index reflects no deduction for fees, expenses or taxes	3.68%	2.85%	[1]	Feb. 29, 2012

[1] For comparative purposes, the value of the Bloomberg Barclays U.S. Intermediate Credit Index and the Bloomberg Barclays U.S. Credit Index on February 29, 2012 is used as the beginning value on March 2, 2012.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Corporate Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and current income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 33.05% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

33.05%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in corporate bonds. The investment adviser uses a disciplined process to select bonds and manage risk. The process includes computer modeling and scenario testing of possible changes in market conditions. The investment adviser will use other techniques in an attempt to manage market risk and duration.

The investment adviser actively manages the fund's bond market and maturity exposure and credit profile. The fund normally invests at least 80% of its assets in bonds rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser, with at least 65% of such investment grade bonds issued by corporations or the U.S. government or its agencies. Generally, the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual bonds of any duration. There are no restrictions on the dollar-weighted average maturity of the fund's portfolio or on the maturities of the individual bonds the fund may purchase. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

In selecting corporate bonds for investment, the fund's portfolio manager analyzes fundamental metrics, including the issuer's cash flow, leverage and operating margins, as well as its business strategy and operating performance, and macro economic factors. The fund typically sells a security when the portfolio manager believes that there has been a negative change in the credit quality of the issuer or has identified a more attractive opportunity or when the portfolio manager seeks to manage the fund's duration or tax position or to provide liquidity to meet shareholder redemptions.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Intermediate Credit Index and the Bloomberg Barclays U.S. Credit Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q1, 2016: 3.28%
Worst Quarter
Q2, 2013: -2.81%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 5.04%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

5.04%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

3.28%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(2.81%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Bloomberg Barclays U.S. Intermediate Credit Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

5.63%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.38%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 29, 2012

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Bloomberg Barclays U.S. Credit Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

3.68%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.85%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Feb. 29, 2012

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.56%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 57

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

179

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

313

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

701

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

57

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

179

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

313

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 701

Annual Return 2013

rr_AnnualReturn2013

(0.66%)

Annual Return 2014

rr_AnnualReturn2014

5.43%

Annual Return 2015

rr_AnnualReturn2015

(0.09%)

Annual Return 2016

rr_AnnualReturn2016

6.43%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.43%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.67%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Mar. 02, 2012

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

4.78%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.26%

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

3.63%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.19%

Class M, Investor Prospectus | BNY Mellon Corporate Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.40%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.81%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 83

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

259

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

450

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,002

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

83

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

259

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

450

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,002

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.08%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.39%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Mar. 02, 2012

[1] For comparative purposes, the value of the Bloomberg Barclays U.S. Intermediate Credit Index and the Bloomberg Barclays U.S. Credit Index on February 29, 2012 is used as the beginning value on March 2, 2012.

XML

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund

Fund Summary - BNY Mellon Short-Term U.S. Government Securities Fund

Investment Objective

The fund seeks to provide as high a level of current income as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Short-Term U.S. Government Securities Fund	Class M Shares	Investor Shares
Investment advisory fees	0.35%	0.35%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.08%	0.08%
Total annual fund operating expenses	0.55%	0.80%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Short-Term U.S. Government Securities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	56	176	307	689
Investor Shares	82	255	444	990

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Short-Term U.S. Government Securities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	56	176	307	689
Investor Shares	82	255	444	990

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 65.98% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in securities issued or guaranteed by the U.S. government or its agencies or instrumentalities, and in repurchase agreements in respect of such securities. The fund may invest in mortgage-related securities issued by U.S. government agencies or instrumentalities. The securities in which the fund invests include those backed by the full faith and credit of the U.S. government and those that are neither insured nor guaranteed by the U.S. government.

Typically in choosing securities, the portfolio manager first examines U.S. and global economic conditions and other market factors in order to estimate long- and short-term interest rates. Using a research-driven investment process, generally the portfolio manager then seeks to identify potentially profitable sectors before they are widely perceived by the market, and seeks underpriced or mispriced securities that appear likely to perform well over time. The fund may engage in frequent trading.

Generally, the fund's average effective portfolio maturity and the average effective duration of the fund's portfolio will be less than three years. The fund may invest in individual bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Interest rate changes may have different effects on the values of mortgage-related securities because of prepayment and extension risks.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Mortgage-related securities risk. Mortgage-related securities are complex derivative instruments, subject to credit, prepayment and extension risk, and may be more volatile, less liquid and more difficult to price accurately than more traditional debt securities. The fund is subject to the credit risk associated with these securities, including the market's perception of the creditworthiness of the issuing federal agency, as well as the credit quality of the underlying assets. Although certain mortgage-related securities are guaranteed as to the timely payment of interest and principal by a third party (such as a U.S. government agency or instrumentality with respect to government-related mortgage-backed securities) the market prices for such securities are not guaranteed and will fluctuate. Declining interest rates may result in the prepayment of higher yielding underlying mortgages and the reinvestment of proceeds at lower interest rates can reduce the fund's potential price gain in response to falling interest rates, reduce the fund's yield and/or cause the fund's share price to fall (prepayment risk). Rising interest rates may result in a drop in prepayments of the underlying mortgages, which would increase the fund's sensitivity to rising interest rates and its potential for price declines (extension risk).

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Government 1-3 Year Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

	Best Quarter Q4, 2008: 3.43% Worst Quarter Q2, 2008: -0.77%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.52%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Short-Term U.S. Government Securities Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	0.42%	0.15%	1.74%
Investor Shares	0.18%	(0.12%)	1.46%
After Taxes on Distributions | Class M Shares	(0.02%)	(0.29%)	1.01%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	0.24%	(0.08%)	1.07%
Bloomberg Barclays U.S. Government 1-3 Year Bond Index reflects no deduction for fees, expenses or taxes	0.87%	0.59%	2.18%

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Short-Term U.S. Government Securities Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to provide as high a level of current income as is consistent with the preservation of capital.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 65.98% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

65.98%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in securities issued or guaranteed by the U.S. government or its agencies or instrumentalities, and in repurchase agreements in respect of such securities. The fund may invest in mortgage-related securities issued by U.S. government agencies or instrumentalities. The securities in which the fund invests include those backed by the full faith and credit of the U.S. government and those that are neither insured nor guaranteed by the U.S. government.

Typically in choosing securities, the portfolio manager first examines U.S. and global economic conditions and other market factors in order to estimate long- and short-term interest rates. Using a research-driven investment process, generally the portfolio manager then seeks to identify potentially profitable sectors before they are widely perceived by the market, and seeks underpriced or mispriced securities that appear likely to perform well over time. The fund may engage in frequent trading.

Generally, the fund's average effective portfolio maturity and the average effective duration of the fund's portfolio will be less than three years. The fund may invest in individual bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Interest rate changes may have different effects on the values of mortgage-related securities because of prepayment and extension risks.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Mortgage-related securities risk. Mortgage-related securities are complex derivative instruments, subject to credit, prepayment and extension risk, and may be more volatile, less liquid and more difficult to price accurately than more traditional debt securities. The fund is subject to the credit risk associated with these securities, including the market's perception of the creditworthiness of the issuing federal agency, as well as the credit quality of the underlying assets. Although certain mortgage-related securities are guaranteed as to the timely payment of interest and principal by a third party (such as a U.S. government agency or instrumentality with respect to government-related mortgage-backed securities) the market prices for such securities are not guaranteed and will fluctuate. Declining interest rates may result in the prepayment of higher yielding underlying mortgages and the reinvestment of proceeds at lower interest rates can reduce the fund's potential price gain in response to falling interest rates, reduce the fund's yield and/or cause the fund's share price to fall (prepayment risk). Rising interest rates may result in a drop in prepayments of the underlying mortgages, which would increase the fund's sensitivity to rising interest rates and its potential for price declines (extension risk).

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

·Short-term trading risk. At times, the fund may engage in short-term trading, which could produce higher transaction costs and taxable distributions and lower the fund's after-tax performance.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Government 1-3 Year Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

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Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

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	Best Quarter Q4, 2008: 3.43% Worst Quarter Q2, 2008: -0.77%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.52%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

0.52%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2008

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

3.43%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(0.77%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Bloomberg Barclays U.S. Government 1-3 Year Bond Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.87%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.59%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.18%

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.55%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 56

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

176

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

307

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

689

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

56

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

176

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

307

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 689

Annual Return 2007

rr_AnnualReturn2007

6.50%

Annual Return 2008

rr_AnnualReturn2008

7.16%

Annual Return 2009

rr_AnnualReturn2009

1.04%

Annual Return 2010

rr_AnnualReturn2010

1.54%

Annual Return 2011

rr_AnnualReturn2011

0.69%

Annual Return 2012

rr_AnnualReturn2012

0.07%

Annual Return 2013

rr_AnnualReturn2013

(0.13%)

Annual Return 2014

rr_AnnualReturn2014

0.23%

Annual Return 2015

rr_AnnualReturn2015

0.14%

Annual Return 2016

rr_AnnualReturn2016

0.42%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.42%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.15%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.74%

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.02%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.29%)

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.01%

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.24%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.08%)

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.07%

Class M, Investor Prospectus | BNY Mellon Short-Term U.S. Government Securities Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.80%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 82

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

255

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

444

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

990

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

82

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

255

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

444

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 990

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.18%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.12%)

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.46%

XML

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund

Fund Summary - BNY Mellon National Intermediate Municipal Bond Fund

Investment Objective

The fund seeks to maximize current income exempt from federal income tax to the extent consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon National Intermediate Municipal Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.35%	0.35%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.03%	0.03%
Total annual fund operating expenses	0.50%	0.75%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon National Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	51	160	280	628
Investor Shares	77	240	417	930

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon National Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	51	160	280	628
Investor Shares	77	240	417	930

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 32.14% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal income tax. Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund’s holdings may be subject to the federal alternative minimum tax.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2009: 6.85%
Worst Quarter
Q4, 2010: -3.71%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 4.20%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon National Intermediate Municipal Bond Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years		Average Annual Returns, 10 Years
Class M Shares	(0.29%)	2.38%		3.72%
Investor Shares	(0.54%)	2.13%		3.47%
After Taxes on Distributions | Class M Shares	(0.49%)	2.33%		3.67%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	1.04%	2.49%		3.64%
S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes	0.01%		[1]		[1]
S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes	0.16%	2.91%		4.43%

[1] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon National Intermediate Municipal Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to maximize current income exempt from federal income tax to the extent consistent with the preservation of capital.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 32.14% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

32.14%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal income tax. Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund’s holdings may be subject to the federal alternative minimum tax.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2009: 6.85%
Worst Quarter
Q4, 2010: -3.71%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 4.20%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

4.20%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

6.85%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2010

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.71%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.01%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

^[1]

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.16%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.91%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.43%

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.50%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 51

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

160

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

280

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

628

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

51

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

160

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

280

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 628

Annual Return 2007

rr_AnnualReturn2007

3.39%

Annual Return 2008

rr_AnnualReturn2008

(1.95%)

Annual Return 2009

rr_AnnualReturn2009

13.49%

Annual Return 2010

rr_AnnualReturn2010

1.81%

Annual Return 2011

rr_AnnualReturn2011

9.33%

Annual Return 2012

rr_AnnualReturn2012

5.26%

Annual Return 2013

rr_AnnualReturn2013

(1.46%)

Annual Return 2014

rr_AnnualReturn2014

5.99%

Annual Return 2015

rr_AnnualReturn2015

2.64%

Annual Return 2016

rr_AnnualReturn2016

(0.29%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.29%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.38%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.72%

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.49%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.33%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.67%

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.04%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.49%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.64%

Class M, Investor Prospectus | BNY Mellon National Intermediate Municipal Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.75%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 77

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

240

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

417

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

930

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

77

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

240

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

417

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 930

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.54%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.13%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.47%

[1] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

XML

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund

Fund Summary - BNY Mellon National Short-Term Municipal Bond Fund

Investment Objective

The fund seeks to maximize current income exempt from federal income tax to the extent consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon National Short-Term Municipal Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.35%	0.35%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.51%	0.76%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon National Short-Term Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	52	164	285	640
Investor Shares	78	243	422	942

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon National Short-Term Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	52	164	285	640
Investor Shares	78	243	422	942

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 35.60% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal income tax. Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity and the average effective duration of the fund's portfolio will be less than three years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Short Index and the S&P Municipal Bond Short Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q1, 2009: 1.93%
Worst Quarter
Q4, 2016: -0.83%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 1.69%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon National Short-Term Municipal Bond Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years		Average Annual Returns, 10 Years
Class M Shares	(0.05%)	0.49%		1.70%
Investor Shares	(0.37%)	0.26%		1.45%
After Taxes on Distributions | Class M Shares	(0.09%)	0.47%		1.69%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	0.36%	0.58%		1.68%
S&P Municipal Bond Investment Grade Short Index reflects no deduction for fees, expenses or taxes	0.34%		[1]		[1]
S&P Municipal Bond Short Index reflects no deduction for fees, expenses or taxes	0.37%	0.95%		2.34%

[1] The S&P Municipal Bond Investment Grade Short Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Short Index until the S&P Municipal Bond Investment Grade Short Index has been calculated for a 10-year period.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon National Short-Term Municipal Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to maximize current income exempt from federal income tax to the extent consistent with the preservation of capital.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 35.60% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

35.60%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal income tax. Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity and the average effective duration of the fund's portfolio will be less than three years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Short Index and the S&P Municipal Bond Short Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q1, 2009: 1.93%
Worst Quarter
Q4, 2016: -0.83%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 1.69%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

1.69%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

1.93%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2016

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(0.83%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | S&P Municipal Bond Investment Grade Short Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.34%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

^[1]

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | S&P Municipal Bond Short Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.37%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.95%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.34%

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.51%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 52

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

164

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

285

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

640

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

52

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

164

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

285

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 640

Annual Return 2007

rr_AnnualReturn2007

3.86%

Annual Return 2008

rr_AnnualReturn2008

1.67%

Annual Return 2009

rr_AnnualReturn2009

5.69%

Annual Return 2010

rr_AnnualReturn2010

1.22%

Annual Return 2011

rr_AnnualReturn2011

2.21%

Annual Return 2012

rr_AnnualReturn2012

1.10%

Annual Return 2013

rr_AnnualReturn2013

0.35%

Annual Return 2014

rr_AnnualReturn2014

0.71%

Annual Return 2015

rr_AnnualReturn2015

0.37%

Annual Return 2016

rr_AnnualReturn2016

(0.05%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.05%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.49%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.70%

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.09%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.47%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.69%

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.36%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.58%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.68%

Class M, Investor Prospectus | BNY Mellon National Short-Term Municipal Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.76%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 78

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

243

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

422

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

942

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

78

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

243

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

422

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 942

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.37%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.26%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.45%

[1] The S&P Municipal Bond Investment Grade Short Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Short Index until the S&P Municipal Bond Investment Grade Short Index has been calculated for a 10-year period.

XML

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund

Fund Summary - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund

Investment Objective

The fund seeks as high a level of current income exempt from federal and Pennsylvania state income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.50%	0.50%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.08%	0.08%
Total annual fund operating expenses	0.70%	0.95%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	72	224	390	871
Investor Shares	97	303	525	1,166

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	72	224	390	871
Investor Shares	97	303	525	1,166

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 20.07% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal and Pennsylvania state personal income taxes. These municipal bonds include those issued by the Commonwealth of Pennsylvania as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal and Pennsylvania state income taxes, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that Pennsylvania's economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2009: 6.64%
Worst Quarter
Q4, 2016: -3.41%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 4.15%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years		Average Annual Returns, 10 Years
Class M Shares		(0.14%)	1.81%		3.12%
Investor Shares		(0.38%)	1.58%		2.87%
After Taxes on Distributions | Class M Shares		(0.54%)	1.64%		3.02%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares		1.29%	2.04%		3.17%
S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes	[1]	0.01%		[2]		[2]
S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes	[1]	0.16%	2.91%		4.43%

[1] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[2] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Pennsylvania Intermediate Municipal Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of current income exempt from federal and Pennsylvania state income taxes as is consistent with the preservation of capital.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 20.07% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

20.07%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal and Pennsylvania state personal income taxes. These municipal bonds include those issued by the Commonwealth of Pennsylvania as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal and Pennsylvania state income taxes, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that Pennsylvania's economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2009: 6.64%
Worst Quarter
Q4, 2016: -3.41%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 4.15%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

4.15%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

6.64%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2016

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.41%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.01%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

^[1],[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

^[1],[2]

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.16%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.91%

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.43%

^[1]

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.70%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 72

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

224

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

390

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

871

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

72

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

224

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

390

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 871

Annual Return 2007

rr_AnnualReturn2007

3.13%

Annual Return 2008

rr_AnnualReturn2008

(3.17%)

Annual Return 2009

rr_AnnualReturn2009

12.10%

Annual Return 2010

rr_AnnualReturn2010

2.22%

Annual Return 2011

rr_AnnualReturn2011

8.60%

Annual Return 2012

rr_AnnualReturn2012

4.53%

Annual Return 2013

rr_AnnualReturn2013

(2.69%)

Annual Return 2014

rr_AnnualReturn2014

5.70%

Annual Return 2015

rr_AnnualReturn2015

1.86%

Annual Return 2016

rr_AnnualReturn2016

(0.14%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.14%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.81%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.12%

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.54%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.64%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.02%

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.29%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.04%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.17%

Class M, Investor Prospectus | BNY Mellon Pennsylvania Intermediate Municipal Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.95%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 97

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

303

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

525

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,166

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

97

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

303

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

525

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,166

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.38%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.58%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.87%

[1] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[2] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

XML

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund

Fund Summary - BNY Mellon Massachusetts Intermediate Municipal Bond Fund

Investment Objective

The fund seeks as high a level of income exempt from federal and Massachusetts state income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Massachusetts Intermediate Municipal Bond Fund	Class M Shares	Investor Shares
Investment advisory fees	0.35%	0.35%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.07%	0.07%
Total annual fund operating expenses	0.54%	0.79%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Massachusetts Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	55	173	302	677
Investor Shares	81	252	439	978

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Massachusetts Intermediate Municipal Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	55	173	302	677
Investor Shares	81	252	439	978

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 31.61% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal and Massachusetts state personal income taxes. These municipal bonds include those issued by the Commonwealth of Massachusetts as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal and Massachusetts state income taxes, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that Massachusetts’ economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2009: 5.30%
Worst Quarter
Q4, 2016: -3.50%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.92%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Massachusetts Intermediate Municipal Bond Fund		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years		Average Annual Returns, 10 Years
Class M Shares		(0.44%)	1.88%		3.37%
Investor Shares		(0.69%)	1.63%		3.11%
After Taxes on Distributions | Class M Shares		(0.69%)	1.76%		3.30%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares		0.97%	2.09%		3.36%
S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes	[1]	0.01%		[2]		[2]
S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes	[1]	0.16%	2.91%		4.43%

[1] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[2] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Massachusetts Intermediate Municipal Bond Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of income exempt from federal and Massachusetts state income taxes as is consistent with the preservation of capital.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 31.61% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

31.61%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

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To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal and Massachusetts state personal income taxes. These municipal bonds include those issued by the Commonwealth of Massachusetts as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years and the average effective duration of the fund's portfolio will not exceed eight years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal and Massachusetts state income taxes, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that Massachusetts’ economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

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The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

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The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

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The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

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The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

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Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

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Best Quarter
Q3, 2009: 5.30%
Worst Quarter
Q4, 2016: -3.50%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.92%.

Year to Date Return, Label

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The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

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Sep. 30, 2017

Bar Chart, Year to Date Return

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3.92%

Highest Quarterly Return, Label

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Best Quarter

Highest Quarterly Return, Date

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Sep. 30, 2009

Highest Quarterly Return

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5.30%

Lowest Quarterly Return, Label

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Worst Quarter

Lowest Quarterly Return, Date

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Dec. 31, 2016

Lowest Quarterly Return

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(3.50%)

Index No Deduction for Fees, Expenses, Taxes [Text]

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reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

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After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

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Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

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Average Annual Returns, 1 Year

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0.01%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

^[1],[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

^[1],[2]

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

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Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.16%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.91%

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.43%

^[1]

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Class M Shares

Risk/Return:

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Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

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0.54%

Expense Example, with Redemption, 1 Year

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$ 55

Expense Example, with Redemption, 3 Years

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173

Expense Example, with Redemption, 5 Years

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302

Expense Example, with Redemption, 10 Years

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677

Expense Example, No Redemption, 1 Year

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55

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

173

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

302

Expense Example, No Redemption, 10 Years

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$ 677

Annual Return 2007

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3.74%

Annual Return 2008

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0.37%

Annual Return 2009

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10.10%

Annual Return 2010

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1.88%

Annual Return 2011

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8.67%

Annual Return 2012

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4.55%

Annual Return 2013

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(2.36%)

Annual Return 2014

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5.50%

Annual Return 2015

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2.37%

Annual Return 2016

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(0.44%)

Average Annual Returns, 1 Year

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(0.44%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.88%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.37%

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

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Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.69%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.76%

Average Annual Returns, 10 Years

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3.30%

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

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Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.97%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.09%

Average Annual Returns, 10 Years

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3.36%

Class M, Investor Prospectus | BNY Mellon Massachusetts Intermediate Municipal Bond Fund | Investor Shares

Risk/Return:

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Investment advisory fees

rr_ManagementFeesOverAssets

0.35%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.07%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.79%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 81

Expense Example, with Redemption, 3 Years

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252

Expense Example, with Redemption, 5 Years

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439

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

978

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

81

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

252

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

439

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 978

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.69%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.63%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.11%

[1] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[2] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

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Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund

Fund Summary - BNY Mellon New York Intermediate Tax-Exempt Bond Fund

Investment Objective

The fund seeks as high a level of income exempt from federal, New York state and New York city income taxes as is consistent with the preservation of capital.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon New York Intermediate Tax-Exempt Bond Fund		Class M	Investor Shares
Investment advisory fees		0.50%	0.50%
Other Expenses - Shareholder services fees		none	0.25%
Other Expenses - Administration fees		0.12%	0.12%
Other Expenses - Other expenses of the fund		0.11%	0.11%
Total annual fund operating expenses		0.73%	0.98%
Fee waiver and/or expense reimbursement	[1]	(0.14%)	(0.14%)
Total annual fund operating expenses (after fee waiver and/or expense reimbursement)		0.59%	0.84%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. The one-year example and the first year of the three-, five- and ten-years examples are based on net operating expenses, which reflect the expense limitation by the fund's investment adviser. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon New York Intermediate Tax-Exempt Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	60	219	392	893
Investor Shares	86	298	528	1,189

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon New York Intermediate Tax-Exempt Bond Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	60	219	392	893
Investor Shares	86	298	528	1,189

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 37.78% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal, New York state and New York city personal income taxes. These municipal bonds include those issued by New York state and New York city as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

The fund normally expects to be fully invested in tax-exempt securities, but may invest up to 20% of its assets in fixed-income securities the income from which is subject to federal income tax, the federal alternative minimum tax, and/or New York state and New York city income taxes.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that New York's economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. Before the fund commenced operations (as of the close of business on September 12, 2008), substantially all of the assets of another investment company advised by an affiliate of the fund's investment adviser, BNY Hamilton Intermediate New York Tax-Exempt Fund (the "predecessor fund"), a series of BNY Hamilton Funds, Inc., that, in all materials respects, had the same investment objective, strategies and policies as the fund, were transferred to the fund in a tax-free reorganization. The performance figures for the fund's Class M shares in the bar chart represent the performance of the predecessor fund's Institutional shares from year to year through September 12, 2008 and the performance of the fund's Class M shares thereafter. The average annual total returns for the fund's Class M shares and Investor shares in the table represent those of the predecessor fund's Institutional shares and Class A shares, respectively, through September 12, 2008 and the performance of the fund's Class M shares and Investor shares thereafter. These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower. These performance figures are compared to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M*

Best Quarter
Q3, 2009: 5.09%
Worst Quarter
Q4, 2016: -3.42%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.93%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon New York Intermediate Tax-Exempt Bond Fund		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years		Average Annual Returns, 10 Years
Class M	[1]	(0.19%)	2.27%		3.74%
Investor Shares	[2]	(0.52%)	2.02%		3.48%
After Taxes on Distributions | Class M	[1]	(0.65%)	2.05%		3.62%
After Taxes on Distributions and Sale of Fund Shares | Class M	[1]	1.19%	2.36%		3.62%
S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes	[3]	0.01%		[4]		[4]
S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes	[3]	0.16%	2.91%		4.43%

[1] The fund's investment adviser has contractually agreed, until December 31, 2018, to waive receipt of its fees and/or assume the expenses of the fund so that the direct expenses of neither class (excluding shareholder services fees, taxes, interest expense, brokerage commissions, commitment fees on borrowings and extraordinary expenses) exceed 0.59%. On or after December 31, 2018, the fund's investment adviser may terminate this expense limitation at any time.

[1] Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

[2] Reflects the performance of the predecessor fund's Class A shares through September 12, 2008.

[3] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[4] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

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Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund

Risk/Return:

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Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon New York Intermediate Tax-Exempt Bond Fund

Objective [Heading]

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Investment Objective

Objective, Primary [Text Block]

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The fund seeks as high a level of income exempt from federal, New York state and New York city income taxes as is consistent with the preservation of capital.

Expense [Heading]

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Fees and Expenses

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

Dec. 31, 2018

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 37.78% of the average value of its portfolio.

Portfolio Turnover, Rate

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37.78%

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. The one-year example and the first year of the three-, five- and ten-years examples are based on net operating expenses, which reflect the expense limitation by the fund's investment adviser. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal Investment Strategy

Strategy Narrative [Text Block]

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To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal bonds that provide income exempt from federal, New York state and New York city personal income taxes. These municipal bonds include those issued by New York state and New York city as well as those issued by territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities.

The fund's investments in municipal and taxable bonds must be rated investment grade (i.e., Baa/BBB or higher) at the time of purchase or, if unrated, deemed of comparable quality by the investment adviser. Generally, the fund's average effective portfolio maturity will be between three and ten years. The fund may invest in individual municipal and taxable bonds of any maturity or duration. A bond's maturity is the length of time until the principal must be fully repaid with interest. Average effective portfolio maturity is an average of the maturities of bonds held by the fund directly and the bonds underlying derivative instruments entered into by the fund, if any, adjusted to reflect provisions or market conditions that may cause a bond's principal to be repaid earlier than at its stated maturity. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

The fund normally expects to be fully invested in tax-exempt securities, but may invest up to 20% of its assets in fixed-income securities the income from which is subject to federal income tax, the federal alternative minimum tax, and/or New York state and New York city income taxes.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·State-specific risk. The fund is subject to the risk that New York's economy, and the revenues underlying its municipal obligations, may decline. Investing primarily in the municipal obligations of a single state makes the fund more sensitive to risks specific to that state and may entail more risk than investing in the municipal obligations of multiple states as a result of potentially less diversification.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

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The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

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The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following bar chart and table provide some indication of the risks of investing in the fund. Before the fund commenced operations (as of the close of business on September 12, 2008), substantially all of the assets of another investment company advised by an affiliate of the fund's investment adviser, BNY Hamilton Intermediate New York Tax-Exempt Fund (the "predecessor fund"), a series of BNY Hamilton Funds, Inc., that, in all materials respects, had the same investment objective, strategies and policies as the fund, were transferred to the fund in a tax-free reorganization. The performance figures for the fund's Class M shares in the bar chart represent the performance of the predecessor fund's Institutional shares from year to year through September 12, 2008 and the performance of the fund's Class M shares thereafter. The average annual total returns for the fund's Class M shares and Investor shares in the table represent those of the predecessor fund's Institutional shares and Class A shares, respectively, through September 12, 2008 and the performance of the fund's Class M shares and Investor shares thereafter. These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower. These performance figures are compared to those of the S&P Municipal Bond Investment Grade Intermediate Index and the S&P Municipal Bond Intermediate Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

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The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

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The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

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Year-by-Year Total Returns as of 12/31 each year (%) Class M*

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

These returns do not reflect the predecessor fund's applicable sales loads for Class A shares, because the fund's shares are not subject to any sales loads. If the predecessor fund's sales loads were reflected, the returns of the fund's Investor shares would be lower.

Bar Chart Closing [Text Block]

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Best Quarter
Q3, 2009: 5.09%
Worst Quarter
Q4, 2016: -3.42%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 3.93%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

3.93%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

5.09%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2016

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.42%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

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After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

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Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | S&P Municipal Bond Investment Grade Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

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Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.01%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

^[1],[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

^[1],[2]

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | S&P Municipal Bond Intermediate Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.16%

^[1]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.91%

^[1]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.43%

^[1]

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Class M

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.11%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.73%

Fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.14%)

^[3]

Total annual fund operating expenses (after fee waiver and/or expense reimbursement)

rr_NetExpensesOverAssets

0.59%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 60

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

219

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

392

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

893

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

60

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

219

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

392

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 893

Annual Return 2007

rr_AnnualReturn2007

4.33%

Annual Return 2008

rr_AnnualReturn2008

2.64%

Annual Return 2009

rr_AnnualReturn2009

8.62%

Annual Return 2010

rr_AnnualReturn2010

1.62%

Annual Return 2011

rr_AnnualReturn2011

9.22%

Annual Return 2012

rr_AnnualReturn2012

5.04%

Annual Return 2013

rr_AnnualReturn2013

(2.32%)

Annual Return 2014

rr_AnnualReturn2014

6.30%

Annual Return 2015

rr_AnnualReturn2015

2.78%

Annual Return 2016

rr_AnnualReturn2016

(0.19%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.19%)

^[4]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.27%

^[4]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.74%

^[4]

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Class M | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.65%)

^[4]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.05%

^[4]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.62%

^[4]

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Class M | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.19%

^[4]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.36%

^[4]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.62%

^[4]

Class M, Investor Prospectus | BNY Mellon New York Intermediate Tax-Exempt Bond Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.11%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.98%

Fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.14%)

^[3]

Total annual fund operating expenses (after fee waiver and/or expense reimbursement)

rr_NetExpensesOverAssets

0.84%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 86

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

298

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

528

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,189

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

86

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

298

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

528

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,189

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.52%)

^[5]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.02%

^[5]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.48%

^[5]

[1] Unlike the fund, the Index is not limited to obligations issued by a single state or municipalities in that state.

[2] The S&P Municipal Bond Investment Grade Intermediate Index was first calculated on March 19, 2013. Accordingly, the fund will continue to report the performance of the S&P Municipal Bond Intermediate Index until the S&P Municipal Bond Investment Grade Intermediate Index has been calculated for a 10-year period.

[3] The fund's investment adviser has contractually agreed, until December 31, 2018, to waive receipt of its fees and/or assume the expenses of the fund so that the direct expenses of neither class (excluding shareholder services fees, taxes, interest expense, brokerage commissions, commitment fees on borrowings and extraordinary expenses) exceed 0.59%. On or after December 31, 2018, the fund's investment adviser may terminate this expense limitation at any time.

[4] Reflects the performance of the predecessor fund's Institutional shares through September 12, 2008.

[5] Reflects the performance of the predecessor fund's Class A shares through September 12, 2008.

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Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund

Fund Summary - BNY Mellon Municipal Opportunities Fund

Investment Objective

The fund seeks to maximize total return consisting of high current income exempt from federal income tax and capital appreciation.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Municipal Opportunities Fund	Class M	Investor
Investment advisory fees	0.50%	0.50%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.11%	0.12%
Total annual fund operating expenses	0.73%	0.99%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Municipal Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	75	233	406	906
Investor	101	315	547	1,213

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Municipal Opportunities Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M	75	233	406	906
Investor	101	315	547	1,213

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 34.78% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in U.S. dollar-denominated fixed-income securities that provide income exempt from federal income tax (municipal bonds). Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities. While the fund typically invests in a diversified portfolio of municipal bonds, it may invest up to 20% of its assets in taxable fixed-income securities, including taxable municipal bonds and non-U.S. dollar-denominated foreign debt securities such as Brady bonds and sovereign debt obligations.

The fund invests at least 80% of its assets in fixed-income securities that are rated investment grade (i.e., Baa/BBB or higher) or are the unrated equivalent as determined by the investment adviser. For additional yield, the fund may invest up to 20% of its assets in fixed-income securities that are rated below investment grade ("high yield" or "junk" bonds) or are the unrated equivalent as determined by the investment adviser. The fund may invest in bonds of any maturity or duration and does not expect to target any specific range of maturity or duration. The dollar-weighted average maturity of the fund's portfolio will vary from time to time depending on the portfolio manager's views on the direction of interest rates. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, interest from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund's portfolio manager seeks to deliver value added excess returns ("alpha") by applying an investment approach designed to identify and exploit relative value opportunities within the municipal bond market and other fixed-income markets.

The fund may, but is not required to, use derivatives, such as options, futures and options on futures (including those relating to securities, indexes, foreign currencies and interest rates), swap agreements and inverse floaters as a substitute for investing directly in an underlying asset, to increase returns, to manage duration, interest rate or foreign currency risk, or as part of a hedging strategy. The fund may buy securities that pay interest at rates that float inversely with changes in prevailing interest rates (inverse floaters). The fund also may make forward commitments in which the fund agrees to buy or sell a security in the future at an agreed upon price. When the fund enters into derivatives transactions, it may be required to segregate liquid assets or enter into offsetting positions or otherwise cover its obligations, in accordance with applicable regulations, while the positions are open.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Unlike investment grade bonds, however, the prices of high yield ("junk") bonds may fluctuate unpredictably and not necessarily inversely with changes in interest rates.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·High yield securities risk. High yield ("junk") securities involve greater credit risk, including the risk of default, than investment grade securities, and are considered predominantly speculative with respect to the issuer's ability to make principal and interest payments. The prices of high yield securities can fall in response to bad news about the issuer or its industry, or the economy in general, to a greater extent than those of higher rated securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. The market for below investment grade securities may be less liquid and therefore these securities may be harder to value or sell at an acceptable price, especially during times of market volatility or decline.Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Derivatives risk. A small investment in derivatives could have a potentially large impact on the fund's performance. The use of derivatives involves risks different from, or possibly greater than, the risks associated with investing directly in the underlying assets, and the fund's use of derivatives may result in losses to the fund. Derivatives in which the fund may invest can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by the fund will not correlate with the underlying assets or the fund's other investments in the manner intended. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. Certain types of derivatives, including over-the-counter transactions, involve greater risks than the underlying assets because, in addition to general market risks, they are subject to liquidity risk, credit and counterparty risk (failure of the counterparty to the derivatives transaction to honor its obligation) and pricing risk (risk that the derivative cannot or will not be accurately valued). Future rules and regulations of the Securities and Exchange Commission (SEC) may require the fund to alter, perhaps materially, its use of derivatives.

·Inverse floating rate securities risk. The interest payment received on inverse floating rate securities generally will decrease when short-term interest rates increase. Inverse floaters are derivatives that involve leverage and could magnify the fund's gains or losses.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund. The ability of a foreign sovereign obligor to make timely payments on its external debt obligations will be strongly influenced by the obligor's balance of payments, including export performance, its access to international credits and investments, fluctuations in interest rates and the extent of its foreign reserves. A governmental obligor may default on its obligations.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Municipal Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2009: 11.23%
Worst Quarter
Q4, 2010: -3.99%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 5.24%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Municipal Opportunities Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class M	(0.11%)	4.31%	7.96%		Oct. 15, 2008
Investor	(0.28%)	4.07%	7.71%		Oct. 15, 2008
After Taxes on Distributions | Class M	(0.15%)	4.07%	7.58%
After Taxes on Distributions and Sale of Fund Shares | Class M	1.47%	4.08%	7.09%
Bloomberg Barclays U.S. Municipal Bond Index reflects no deduction for fees, expenses or taxes	0.25%	3.28%	5.16%	[1]	Sep. 30, 2008

[1] For comparative purposes, the value of the Index on September 30, 2008 is used as the beginning value on October 15, 2008.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Municipal Opportunities Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to maximize total return consisting of high current income exempt from federal income tax and capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 34.78% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

34.78%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in U.S. dollar-denominated fixed-income securities that provide income exempt from federal income tax (municipal bonds). Municipal bonds are debt securities or other obligations issued by states, territories and possessions of the United States and the District of Columbia and their political subdivisions, agencies and instrumentalities, or multistate agencies and authorities, and certain other specified securities. While the fund typically invests in a diversified portfolio of municipal bonds, it may invest up to 20% of its assets in taxable fixed-income securities, including taxable municipal bonds and non-U.S. dollar-denominated foreign debt securities such as Brady bonds and sovereign debt obligations.

The fund invests at least 80% of its assets in fixed-income securities that are rated investment grade (i.e., Baa/BBB or higher) or are the unrated equivalent as determined by the investment adviser. For additional yield, the fund may invest up to 20% of its assets in fixed-income securities that are rated below investment grade ("high yield" or "junk" bonds) or are the unrated equivalent as determined by the investment adviser. The fund may invest in bonds of any maturity or duration and does not expect to target any specific range of maturity or duration. The dollar-weighted average maturity of the fund's portfolio will vary from time to time depending on the portfolio manager's views on the direction of interest rates. A bond's maturity is the length of time until the principal must be fully repaid with interest. Dollar-weighted average maturity is an average of the stated maturities of the securities held by the fund, based on their dollar-weighted proportions in the fund. Duration is an indication of an investment's "interest rate risk," or how sensitive a bond or the fund's portfolio may be to changes in interest rates.

Although the fund seeks to provide income exempt from federal income tax, interest from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund's portfolio manager seeks to deliver value added excess returns ("alpha") by applying an investment approach designed to identify and exploit relative value opportunities within the municipal bond market and other fixed-income markets.

The fund may, but is not required to, use derivatives, such as options, futures and options on futures (including those relating to securities, indexes, foreign currencies and interest rates), swap agreements and inverse floaters as a substitute for investing directly in an underlying asset, to increase returns, to manage duration, interest rate or foreign currency risk, or as part of a hedging strategy. The fund may buy securities that pay interest at rates that float inversely with changes in prevailing interest rates (inverse floaters). The fund also may make forward commitments in which the fund agrees to buy or sell a security in the future at an agreed upon price. When the fund enters into derivatives transactions, it may be required to segregate liquid assets or enter into offsetting positions or otherwise cover its obligations, in accordance with applicable regulations, while the positions are open.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Municipal securities risk. The amount of public information available about municipal securities is generally less than that for corporate equities or bonds. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or value of the fund's investments in municipal securities. Other factors include the general conditions of the municipal securities market, the size of the particular offering, the maturity of the obligation and the rating of the issue. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk and fund expenses. Changes in economic, business or political conditions relating to a particular municipal project, municipality, or state, territory or possession of the United States in which the fund invests may have an impact on the fund's share price.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Unlike investment grade bonds, however, the prices of high yield ("junk") bonds may fluctuate unpredictably and not necessarily inversely with changes in interest rates.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·High yield securities risk. High yield ("junk") securities involve greater credit risk, including the risk of default, than investment grade securities, and are considered predominantly speculative with respect to the issuer's ability to make principal and interest payments. The prices of high yield securities can fall in response to bad news about the issuer or its industry, or the economy in general, to a greater extent than those of higher rated securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. The market for below investment grade securities may be less liquid and therefore these securities may be harder to value or sell at an acceptable price, especially during times of market volatility or decline.Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·Derivatives risk. A small investment in derivatives could have a potentially large impact on the fund's performance. The use of derivatives involves risks different from, or possibly greater than, the risks associated with investing directly in the underlying assets, and the fund's use of derivatives may result in losses to the fund. Derivatives in which the fund may invest can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by the fund will not correlate with the underlying assets or the fund's other investments in the manner intended. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. Certain types of derivatives, including over-the-counter transactions, involve greater risks than the underlying assets because, in addition to general market risks, they are subject to liquidity risk, credit and counterparty risk (failure of the counterparty to the derivatives transaction to honor its obligation) and pricing risk (risk that the derivative cannot or will not be accurately valued). Future rules and regulations of the Securities and Exchange Commission (SEC) may require the fund to alter, perhaps materially, its use of derivatives.

·Inverse floating rate securities risk. The interest payment received on inverse floating rate securities generally will decrease when short-term interest rates increase. Inverse floaters are derivatives that involve leverage and could magnify the fund's gains or losses.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund. The ability of a foreign sovereign obligor to make timely payments on its external debt obligations will be strongly influenced by the obligor's balance of payments, including export performance, its access to international credits and investments, fluctuations in interest rates and the extent of its foreign reserves. A governmental obligor may default on its obligations.

·Non-diversification risk. The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The fund is non-diversified, which means that the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, the fund's performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Bloomberg Barclays U.S. Municipal Bond Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2009: 11.23%
Worst Quarter
Q4, 2010: -3.99%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 5.24%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

5.24%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

11.23%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2010

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.99%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Bloomberg Barclays U.S. Municipal Bond Index reflects no deduction for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.25%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.28%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.16%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2008

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Class M

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.11%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.73%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 75

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

233

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

406

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

906

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

75

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

233

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

406

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 906

Annual Return 2009

rr_AnnualReturn2009

23.06%

Annual Return 2010

rr_AnnualReturn2010

3.52%

Annual Return 2011

rr_AnnualReturn2011

11.05%

Annual Return 2012

rr_AnnualReturn2012

10.79%

Annual Return 2013

rr_AnnualReturn2013

(3.12%)

Annual Return 2014

rr_AnnualReturn2014

11.54%

Annual Return 2015

rr_AnnualReturn2015

3.24%

Annual Return 2016

rr_AnnualReturn2016

(0.11%)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.11%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.31%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.96%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 15, 2008

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Class M | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.15%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.07%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.58%

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Class M | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.47%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.08%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.09%

Class M, Investor Prospectus | BNY Mellon Municipal Opportunities Fund | Investor

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.50%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.12%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.99%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 101

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

315

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

547

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,213

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

101

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

315

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

547

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,213

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

(0.28%)

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.07%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.71%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 15, 2008

[1] For comparative purposes, the value of the Index on September 30, 2008 is used as the beginning value on October 15, 2008.

XML

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund

Fund Summary - BNY Mellon Asset Allocation Fund

Investment Objective

The fund seeks long-term growth of principal in conjunction with current income.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Asset Allocation Fund		Class M Shares	Investor Shares
Investment advisory fees	[1]	0.30%	0.30%
Other Expenses - Shareholder services fees		none	0.25%
Other Expenses - Administration fees		0.05%	0.05%
Other Expenses - Other expenses of the fund		0.03%	0.03%
Acquired fund fees and expenses	[2]	0.57%	0.57%
Total annual fund operating expenses		0.95%	1.20%
Fee waiver and/or expense reimbursement	[3]	(0.08%)	(0.08%)
Total annual fund operating expenses (after fee waiver and/or expense reimbursement)		0.87%	1.12%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. The one-year example and the first year of the three-, five- and ten-years examples are based on net operating expenses, which reflect the expense limitation by the fund's investment adviser. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Asset Allocation Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	89	295	518	1,159
Investor Shares	114	373	652	1,447

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Asset Allocation Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	89	295	518	1,159
Investor Shares	114	373	652	1,447

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 27.34% of the average value of its portfolio.

Principal Investment Strategy

The fund may invest in both individual securities and other investment companies, including other BNY Mellon funds, funds in the Dreyfus Family of Funds and unaffiliated open-end funds, closed-end funds and exchange-traded funds (referred to below as the "underlying funds"), which in turn may invest directly in the asset classes described below. To pursue its goal, the fund currently intends to allocate its assets, directly and/or through investment in the underlying funds, to gain investment exposure to the following asset classes: Large Cap Equities, Small Cap and Mid Cap Equities, Developed International and Global Equities, Emerging Markets Equities, Investment Grade Bonds, High Yield Bonds, Emerging Markets Debt, Diversifying Strategies and Money Market Instruments.

The fund's investment adviser allocates the fund's investments (directly and/or through investment in the underlying funds) among these asset classes using fundamental and quantitative analysis, and its outlook for the economy and financial markets. The underlying funds are selected by the fund's investment adviser based on their investment objectives and management policies, portfolio holdings, risk/reward profiles, historical performance, and other factors, including the correlation and covariance among the underlying funds. The fund may change the underlying funds – whether affiliated or unaffiliated – from time to time without notice to fund shareholders. The fund may invest directly in the equity securities of large-cap companies (generally those with total market capitalizations of $5 billion or more) and in fixed-income securities rated investment grade (i.e., Baa/BBB or higher) or, if unrated, deemed to be of comparable quality by the investment adviser, at the time of purchase.

The fund is not required to maintain exposure to any particular asset class and the investment adviser determines whether to invest in a particular asset class and whether to invest directly in securities or through an underlying fund, and sets the target allocations. The asset classes and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the asset classes, and the underlying funds selected by the investment adviser as fund investment options as of the date of this prospectus were as follows:

Asset Class	Target	Range
Large Cap EquitiesDirect InvestmentsBNY Mellon Focused Equity Opportunities FundBNY Mellon Income Stock FundDreyfus Appreciation Fund, Inc.Dreyfus U.S. Equity FundDreyfus Research Growth Fund, Inc.Dreyfus Strategic Value Fund	36%	20% to 45%
Small Cap and Mid Cap EquitiesBNY Mellon Mid Cap Multi-Strategy FundBNY Mellon Small/Mid Cap Multi-Strategy FundBNY Mellon Small Cap Multi-Strategy FundDreyfus Select Managers Small Cap Value FundDreyfus Select Managers Small Cap Growth Fund	14%	5% to 20%
Developed International and Global Equities BNY Mellon International Fund Dreyfus/Newton International Equity Fund Global Stock Fund (Dreyfus) International Stock Fund (Dreyfus) Dreyfus Global Real Estate Securities Fund Dreyfus International Small Cap Fund	10%	5% to 20%
Emerging Markets EquitiesBNY Mellon Emerging Markets Fund	5%	0% to 20%
Investment Grade BondsDirect InvestmentsBNY Mellon Short-Term U.S. Government Securities FundBNY Mellon Intermediate Bond FundBNY Mellon Corporate Bond FundDreyfus Inflation Adjusted Securities Fund	22%	20% to 55%

Asset Class	Target	Range
High Yield Bonds Dreyfus High Yield Fund Dreyfus Floating Rate Income Fund	4%	0% to 10%
Emerging Markets DebtUnaffiliated Investment Company	2%	0% to 10%
Diversifying Strategies Dynamic Total Return Fund (Dreyfus) Unaffiliated Investment Companies	6%	0% to 20%
Money Market InstrumentsDirect Investments	1%	0% to 10%

The asset classes and the target weightings and ranges have been selected for investment over longer time periods based on the investment adviser's expectation that the selected securities and underlying funds, in combination, will be appropriate to achieve the fund's investment objective. The target weightings will deviate over the short term because of market movements and fund cash flows. If appreciation or depreciation in the value of selected securities or an underlying fund's shares causes the percentage of the fund's assets invested in an asset class to fall outside the applicable investment range, the investment adviser will consider whether to reallocate the fund's assets, but is not required to do so. The investment adviser normally considers reallocating the fund's investments at least quarterly, but may do so more often in response to market conditions. Any changes to the asset classes, underlying funds or the allocation weightings may be implemented over a reasonable period of time. The investment adviser has the discretion to change the asset classes, whether to invest directly in securities or through an underlying fund, and the target allocations and ranges, without shareholder approval or prior notice, when the investment adviser deems it appropriate. To the extent an underlying fund offers multiple classes of shares, the fund will purchase shares of the class with the lowest expense ratio and without a sales load or distribution and/or service fee.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

The fund invests in shares of the underlying funds and thus the fund is subject to the same principal investment risks as the underlying funds in which it invests, which are described in the fund's prospectus and/or below. For more information regarding these risks, see the prospectus for the specific underlying fund. The fund's investments in shares of the underlying funds may involve duplication of advisory fees and certain other expenses.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among the asset classes and the underlying funds. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal. The underlying funds may not achieve their investment objectives, and their performance may be lower than that of the asset class the underlying funds were selected to represent.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Correlation risk. Because the fund allocates its investments among different asset classes, the fund is subject to correlation risk. Although the prices of equity securities and fixed-income securities, as well as other asset classes, often rise and fall at different times so that a fall in the price of one may be offset by a rise in the price of the other, in down markets the prices of these securities and asset classes can also fall in tandem.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund. Securities of issuers located in emerging markets can be more volatile and less liquid than those of issuers in more developed economies.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Unlike investment grade bonds, however, the prices of high yield ("junk") bonds may fluctuate unpredictably and not necessarily inversely with changes in interest rates. In addition, the rates on floating rate instruments adjust periodically with changes in market interest rates. Although these instruments are generally less sensitive to interest rate changes than fixed rate instruments, the value of floating rate loans and other floating rate securities may decline if their interest rates do not rise as quickly, or as much, as general interest rates.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·High yield securities risk. High yield ("junk") securities involve greater credit risk, including the risk of default, than investment grade securities, and are considered predominantly speculative with respect to the issuer's ability to make principal and interest payments. The prices of high yield securities can fall in response to bad news about the issuer or its industry, or the economy in general, to a greater extent than those of higher rated securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. The market for below investment grade securities may be less liquid and therefore these securities may be harder to value or sell at an acceptable price, especially during times of market volatility or decline. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities. No active trading market may exist for some of the floating rate loans in which the fund invests and certain loans may be subject to restrictions on resale. Because some floating rate loans that the fund invests in may have a more limited secondary market, liquidity risk is more pronounced for the fund than for mutual funds that invest primarily in other types of fixed-income instruments or equity securities. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·ETF and other investment company risk. To the extent the fund invests in pooled investment vehicles, such as ETFs and other investment companies, the fund will be affected by the investment policies, practices and performance of such entities in direct proportion to the amount of assets the fund has invested therein. The risks of investing in other investment companies, including ETFs, typically reflect the risks associated with the types of instruments in which the investment companies invest. When the fund invests in an ETF or other investment company, shareholders of the fund will bear indirectly their proportionate share of the expenses of the ETF or other investment company (including management fees) in addition to the expenses of the fund. ETFs are exchange-traded investment companies that are, in many cases, designed to provide investment results corresponding to an index. The value of the underlying securities can fluctuate in response to activities of individual companies or in response to general market and/or economic conditions. Additional risks of investments in ETFs include: (i) the market price of an ETF's shares may trade at a discount to its net asset value; (ii) an active trading market for an ETF's shares may not develop or be maintained; or (iii) trading may be halted if the listing exchanges' officials deem such action appropriate, the shares are delisted from the exchange, or the activation of market-wide "circuit breakers" (which are tied to large decreases in stock prices) halts trading generally. The fund will incur brokerage costs when purchasing and selling shares of ETFs.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Morningstar Moderate Target Risk Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on September 15, 2011. Prior to that date, the fund invested in individual securities and BNY Mellon funds only and its target allocation was 60% of its assets invested in equity securities (directly and through underlying funds) and 40% of its assets invested in bonds and money market instruments (directly), with a range of 15% above or below such target amount. Different investment strategies may lead to different performance results. The fund's performance for periods prior to September 15, 2011 shown in the bar chart and table reflects the investment strategy in effect prior to that date.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

	Best Quarter Q3, 2009: 12.14% Worst Quarter Q3, 2011: -13.21%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 11.93%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Asset Allocation Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	6.05%	7.43%	4.60%
Investor Shares	5.88%	7.20%	4.35%
After Taxes on Distributions | Class M Shares	5.26%	5.94%	3.26%
After Taxes on Distributions and Sale of Fund Shares | Class M Shares	3.85%	5.57%	3.40%
Morningstar Moderate Target Risk Index reflects no deduction for fees, expenses or taxes	8.57%	7.44%	5.23%

[1] The fund has agreed to pay an investment advisory fee at the rate of 0.65% applied to that portion of its average daily net assets allocated to direct investments in equity securities, at the rate of 0.40% applied to that portion of its average daily net assets allocated to direct investments in debt securities, and at the rate of 0.15% applied to that portion of its average daily net assets allocated to money market instruments or the underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

[3] The fund's investment adviser has contractually agreed, until December 31, 2018, to waive receipt of its fees and/or assume the expenses of the fund so that the total annual fund operating expenses of neither class (excluding shareholder services fees, taxes, interest, brokerage commissions, commitment fees on borrowings and extraordinary expenses) exceed 0.87%. On or after December 31, 2018, the fund's investment adviser may terminate this expense limitation at any time.

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Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund

Risk/Return:

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Risk/Return [Heading]

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Fund Summary - BNY Mellon Asset Allocation Fund

Objective [Heading]

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Investment Objective

Objective, Primary [Text Block]

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The fund seeks long-term growth of principal in conjunction with current income.

Expense [Heading]

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Fees and Expenses

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

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Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

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Dec. 31, 2018

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 27.34% of the average value of its portfolio.

Portfolio Turnover, Rate

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27.34%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

"Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. The one-year example and the first year of the three-, five- and ten-years examples are based on net operating expenses, which reflect the expense limitation by the fund's investment adviser. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal Investment Strategy

Strategy Narrative [Text Block]

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The fund may invest in both individual securities and other investment companies, including other BNY Mellon funds, funds in the Dreyfus Family of Funds and unaffiliated open-end funds, closed-end funds and exchange-traded funds (referred to below as the "underlying funds"), which in turn may invest directly in the asset classes described below. To pursue its goal, the fund currently intends to allocate its assets, directly and/or through investment in the underlying funds, to gain investment exposure to the following asset classes: Large Cap Equities, Small Cap and Mid Cap Equities, Developed International and Global Equities, Emerging Markets Equities, Investment Grade Bonds, High Yield Bonds, Emerging Markets Debt, Diversifying Strategies and Money Market Instruments.

The fund's investment adviser allocates the fund's investments (directly and/or through investment in the underlying funds) among these asset classes using fundamental and quantitative analysis, and its outlook for the economy and financial markets. The underlying funds are selected by the fund's investment adviser based on their investment objectives and management policies, portfolio holdings, risk/reward profiles, historical performance, and other factors, including the correlation and covariance among the underlying funds. The fund may change the underlying funds – whether affiliated or unaffiliated – from time to time without notice to fund shareholders. The fund may invest directly in the equity securities of large-cap companies (generally those with total market capitalizations of $5 billion or more) and in fixed-income securities rated investment grade (i.e., Baa/BBB or higher) or, if unrated, deemed to be of comparable quality by the investment adviser, at the time of purchase.

The fund is not required to maintain exposure to any particular asset class and the investment adviser determines whether to invest in a particular asset class and whether to invest directly in securities or through an underlying fund, and sets the target allocations. The asset classes and the fund's targets and ranges (expressed as a percentage of the fund's investable assets) for allocating its assets among the asset classes, and the underlying funds selected by the investment adviser as fund investment options as of the date of this prospectus were as follows:

Asset Class	Target	Range
Large Cap EquitiesDirect InvestmentsBNY Mellon Focused Equity Opportunities FundBNY Mellon Income Stock FundDreyfus Appreciation Fund, Inc.Dreyfus U.S. Equity FundDreyfus Research Growth Fund, Inc.Dreyfus Strategic Value Fund	36%	20% to 45%
Small Cap and Mid Cap EquitiesBNY Mellon Mid Cap Multi-Strategy FundBNY Mellon Small/Mid Cap Multi-Strategy FundBNY Mellon Small Cap Multi-Strategy FundDreyfus Select Managers Small Cap Value FundDreyfus Select Managers Small Cap Growth Fund	14%	5% to 20%
Developed International and Global Equities BNY Mellon International Fund Dreyfus/Newton International Equity Fund Global Stock Fund (Dreyfus) International Stock Fund (Dreyfus) Dreyfus Global Real Estate Securities Fund Dreyfus International Small Cap Fund	10%	5% to 20%
Emerging Markets EquitiesBNY Mellon Emerging Markets Fund	5%	0% to 20%
Investment Grade BondsDirect InvestmentsBNY Mellon Short-Term U.S. Government Securities FundBNY Mellon Intermediate Bond FundBNY Mellon Corporate Bond FundDreyfus Inflation Adjusted Securities Fund	22%	20% to 55%

Asset Class	Target	Range
High Yield Bonds Dreyfus High Yield Fund Dreyfus Floating Rate Income Fund	4%	0% to 10%
Emerging Markets DebtUnaffiliated Investment Company	2%	0% to 10%
Diversifying Strategies Dynamic Total Return Fund (Dreyfus) Unaffiliated Investment Companies	6%	0% to 20%
Money Market InstrumentsDirect Investments	1%	0% to 10%

The asset classes and the target weightings and ranges have been selected for investment over longer time periods based on the investment adviser's expectation that the selected securities and underlying funds, in combination, will be appropriate to achieve the fund's investment objective. The target weightings will deviate over the short term because of market movements and fund cash flows. If appreciation or depreciation in the value of selected securities or an underlying fund's shares causes the percentage of the fund's assets invested in an asset class to fall outside the applicable investment range, the investment adviser will consider whether to reallocate the fund's assets, but is not required to do so. The investment adviser normally considers reallocating the fund's investments at least quarterly, but may do so more often in response to market conditions. Any changes to the asset classes, underlying funds or the allocation weightings may be implemented over a reasonable period of time. The investment adviser has the discretion to change the asset classes, whether to invest directly in securities or through an underlying fund, and the target allocations and ranges, without shareholder approval or prior notice, when the investment adviser deems it appropriate. To the extent an underlying fund offers multiple classes of shares, the fund will purchase shares of the class with the lowest expense ratio and without a sales load or distribution and/or service fee.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

The fund invests in shares of the underlying funds and thus the fund is subject to the same principal investment risks as the underlying funds in which it invests, which are described in the fund's prospectus and/or below. For more information regarding these risks, see the prospectus for the specific underlying fund. The fund's investments in shares of the underlying funds may involve duplication of advisory fees and certain other expenses.

·Strategy allocation risk. The ability of the fund to achieve its investment goal depends, in part, on the ability of the investment adviser to allocate effectively the fund's assets among the asset classes and the underlying funds. There can be no assurance that the actual allocations will be effective in achieving the fund's investment goal. The underlying funds may not achieve their investment objectives, and their performance may be lower than that of the asset class the underlying funds were selected to represent.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Correlation risk. Because the fund allocates its investments among different asset classes, the fund is subject to correlation risk. Although the prices of equity securities and fixed-income securities, as well as other asset classes, often rise and fall at different times so that a fall in the price of one may be offset by a rise in the price of the other, in down markets the prices of these securities and asset classes can also fall in tandem.

·Conflicts of interest risk. The fund's investment adviser will have the authority to change the investment strategies, including whether to implement a strategy by investing directly in securities or through an underlying fund. The fund's investment adviser or its affiliates may serve as investment adviser to the underlying funds. The interests of the fund on the one hand, and those of an underlying fund on the other, will not always be the same. Therefore, conflicts may arise as the investment adviser fulfills its fiduciary duty to the fund and the underlying funds. In addition, the investment adviser recommends asset allocations among these underlying funds, each of which pays advisory fees at different rates to the investment adviser or its affiliates. These situations are considered by the fund's board when it reviews the asset allocations for the fund.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Small and midsize company risk. Small and midsize companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies. The shares of smaller companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the fund's ability to sell these securities.

·Foreign investment risk. To the extent the fund invests in foreign securities, the fund's performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund. Securities of issuers located in emerging markets can be more volatile and less liquid than those of issuers in more developed economies.

·Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies, potentially making prompt liquidation at an attractive price difficult. The economies of countries with emerging markets may be based predominantly on only a few industries, may be highly vulnerable to changes in local or global trade conditions, and may suffer from extreme debt burdens or volatile inflation rates. Transaction settlement and dividend collection procedures also may be less reliable in emerging markets than in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States.

·Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

·Fixed-income market risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates), which currently are at or near historic lows in the United States and in other countries. An unexpected increase in fund redemption requests, including requests from shareholders who may own a significant percentage of the fund's shares, which may be triggered by market turmoil or an increase in interest rates, could cause the fund to sell its holdings at a loss or at undesirable prices and adversely affect the fund's share price and increase the fund's liquidity risk, fund expenses and/or taxable distributions.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Prepayment risk. Some securities give the issuer the option to prepay or call the securities before their maturity date, which may reduce the market value of the security and the anticipated yield-to-maturity. Issuers often exercise this right when interest rates fall. If an issuer "calls" its securities during a time of declining interest rates, the fund might have to reinvest the proceeds in an investment offering a lower yield, and therefore might not benefit from any increase in value as a result of declining interest rates. During periods of market illiquidity or rising interest rates, prices of "callable" issues are subject to increased price fluctuation.

·Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund's investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the values of already-issued fixed rate fixed-income securities generally rise. However, when interest rates fall, the fund's investments in new securities may be at lower yields and may reduce the fund's income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates. For example, the market price of a fixed-income security with a duration of three years would be expected to decline 3% if interest rates rose 1%. Conversely, the market price of the same security would be expected to increase 3% if interest rates fell 1%. Risks associated with rising interest rates are heightened given that interest rates in the United States and other countries currently are at or near historic lows. Unlike investment grade bonds, however, the prices of high yield ("junk") bonds may fluctuate unpredictably and not necessarily inversely with changes in interest rates. In addition, the rates on floating rate instruments adjust periodically with changes in market interest rates. Although these instruments are generally less sensitive to interest rate changes than fixed rate instruments, the value of floating rate loans and other floating rate securities may decline if their interest rates do not rise as quickly, or as much, as general interest rates.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security's price to fall, lowering the value of the fund's investment in such security. The lower a security's credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

·High yield securities risk. High yield ("junk") securities involve greater credit risk, including the risk of default, than investment grade securities, and are considered predominantly speculative with respect to the issuer's ability to make principal and interest payments. The prices of high yield securities can fall in response to bad news about the issuer or its industry, or the economy in general, to a greater extent than those of higher rated securities.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund's share price may fall dramatically, even during periods of declining interest rates. The secondary market for certain municipal bonds tends to be less well developed or liquid than many other securities markets, which may adversely affect the fund's ability to sell such municipal bonds at attractive prices. Investments that are illiquid or that trade in lower volumes may be more difficult to value. The market for below investment grade securities may be less liquid and therefore these securities may be harder to value or sell at an acceptable price, especially during times of market volatility or decline. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities. No active trading market may exist for some of the floating rate loans in which the fund invests and certain loans may be subject to restrictions on resale. Because some floating rate loans that the fund invests in may have a more limited secondary market, liquidity risk is more pronounced for the fund than for mutual funds that invest primarily in other types of fixed-income instruments or equity securities. Liquidity risk also may refer to the risk that the fund will not be able to pay redemption proceeds within the allowable time period stated in this prospectus because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. To meet redemption requests, the fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions, which may adversely affect the fund's share price.

·ETF and other investment company risk. To the extent the fund invests in pooled investment vehicles, such as ETFs and other investment companies, the fund will be affected by the investment policies, practices and performance of such entities in direct proportion to the amount of assets the fund has invested therein. The risks of investing in other investment companies, including ETFs, typically reflect the risks associated with the types of instruments in which the investment companies invest. When the fund invests in an ETF or other investment company, shareholders of the fund will bear indirectly their proportionate share of the expenses of the ETF or other investment company (including management fees) in addition to the expenses of the fund. ETFs are exchange-traded investment companies that are, in many cases, designed to provide investment results corresponding to an index. The value of the underlying securities can fluctuate in response to activities of individual companies or in response to general market and/or economic conditions. Additional risks of investments in ETFs include: (i) the market price of an ETF's shares may trade at a discount to its net asset value; (ii) an active trading market for an ETF's shares may not develop or be maintained; or (iii) trading may be halted if the listing exchanges' officials deem such action appropriate, the shares are delisted from the exchange, or the activation of market-wide "circuit breakers" (which are tied to large decreases in stock prices) halts trading generally. The fund will incur brokerage costs when purchasing and selling shares of ETFs.

·Issuer risk. A security's market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer's products or services, or factors that affect the issuer's industry, such as labor shortages or increased production costs and competitive conditions within an industry.

Risk Lose Money [Text]

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The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows the performance of the fund's Class M shares from year to year. The table compares the average annual total returns of the fund's Class M shares and Investor shares to those of the Morningstar Moderate Target Risk Index.

After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary. After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses. The fund changed its investment strategy on September 15, 2011. Prior to that date, the fund invested in individual securities and BNY Mellon funds only and its target allocation was 60% of its assets invested in equity securities (directly and through underlying funds) and 40% of its assets invested in bonds and money market instruments (directly), with a range of 15% above or below such target amount. Different investment strategies may lead to different performance results. The fund's performance for periods prior to September 15, 2011 shown in the bar chart and table reflects the investment strategy in effect prior to that date.

Performance Information Illustrates Variability of Returns [Text]

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The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

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The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

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Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

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	Best Quarter Q3, 2009: 12.14% Worst Quarter Q3, 2011: -13.21%
The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 11.93%.

Year to Date Return, Label

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The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

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11.93%

Highest Quarterly Return, Label

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Best Quarter

Highest Quarterly Return, Date

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Sep. 30, 2009

Highest Quarterly Return

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12.14%

Lowest Quarterly Return, Label

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Worst Quarter

Lowest Quarterly Return, Date

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Sep. 30, 2011

Lowest Quarterly Return

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(13.21%)

Index No Deduction for Fees, Expenses, Taxes [Text]

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reflects no deduction for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

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After-tax performance is shown only for Class M shares. After-tax performance of the fund's Investor shares will vary.

Caption

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Average Annual Total Returns as of 12/31/16

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Morningstar Moderate Target Risk Index reflects no deduction for fees, expenses or taxes

Risk/Return:

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Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.57%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.44%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.23%

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.30%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.05%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.57%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

0.95%

Fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[3]

Total annual fund operating expenses (after fee waiver and/or expense reimbursement)

rr_NetExpensesOverAssets

0.87%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 89

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

295

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

518

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,159

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

89

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

295

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

518

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,159

Annual Return 2007

rr_AnnualReturn2007

9.29%

Annual Return 2008

rr_AnnualReturn2008

(23.01%)

Annual Return 2009

rr_AnnualReturn2009

21.55%

Annual Return 2010

rr_AnnualReturn2010

12.65%

Annual Return 2011

rr_AnnualReturn2011

(4.92%)

Annual Return 2012

rr_AnnualReturn2012

12.15%

Annual Return 2013

rr_AnnualReturn2013

15.43%

Annual Return 2014

rr_AnnualReturn2014

5.91%

Annual Return 2015

rr_AnnualReturn2015

(1.58%)

Annual Return 2016

rr_AnnualReturn2016

6.05%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.05%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.43%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.60%

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Class M Shares | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

5.26%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.94%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.26%

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Class M Shares | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

3.85%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.57%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.40%

Class M, Investor Prospectus | BNY Mellon Asset Allocation Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.30%

^[1]

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.05%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.03%

Acquired fund fees and expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.57%

^[2]

Total annual fund operating expenses

rr_ExpensesOverAssets

1.20%

Fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.08%)

^[3]

Total annual fund operating expenses (after fee waiver and/or expense reimbursement)

rr_NetExpensesOverAssets

1.12%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 114

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

373

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

652

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,447

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

114

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

373

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

652

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,447

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

5.88%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.20%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.35%

[1] The fund has agreed to pay an investment advisory fee at the rate of 0.65% applied to that portion of its average daily net assets allocated to direct investments in equity securities, at the rate of 0.40% applied to that portion of its average daily net assets allocated to direct investments in debt securities, and at the rate of 0.15% applied to that portion of its average daily net assets allocated to money market instruments or the underlying funds.

[2] "Acquired fund fees and expenses" are incurred indirectly by the fund as a result of its investment in investment companies. These fees and expenses are not included in the Financial Highlights tables; accordingly, total annual fund operating expenses do not correlate to the ratio of expenses to average net assets in the Financial Highlights tables.

[3] The fund's investment adviser has contractually agreed, until December 31, 2018, to waive receipt of its fees and/or assume the expenses of the fund so that the total annual fund operating expenses of neither class (excluding shareholder services fees, taxes, interest, brokerage commissions, commitment fees on borrowings and extraordinary expenses) exceed 0.87%. On or after December 31, 2018, the fund's investment adviser may terminate this expense limitation at any time.

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Class M, Investor Prospectus | BNY Mellon Government Money Market Fund

Fund Summary - BNY Mellon Government Money Market Fund

Investment Objective

The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon Government Money Market Fund	Class M Shares	Investor Shares
Investment advisory fees	0.15%	0.15%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.04%
Total annual fund operating expenses	0.31%	0.56%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon Government Money Market Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	32	100	174	393
Investor Shares	57	179	313	701

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon Government Money Market Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	32	100	174	393
Investor Shares	57	179	313	701

Principal Investment Strategy

The fund pursues its investment objective by investing only in government securities (i.e., securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, including those with floating or variable rates of interest), repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

The fund is a "government money market fund," as that term is defined in Rule 2a-7, and as such is required to invest at least 99.5% of its total assets in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in government securities and repurchase agreements collateralized solely by government securities (i.e., under normal circumstances, the fund will not invest more than 20% of its net assets in cash and/or repurchase agreements collateralized by cash). The securities in which the fund invests include those backed by the full faith and credit of the U.S. government, which include U.S. Treasury securities as well as securities issued by certain agencies of the U.S. government, and those that are neither insured nor guaranteed by the U.S. government.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund currently is not permitted to impose a fee upon the sale of shares (a "liquidity fee") or temporarily suspend redemptions (a redemption "gate") under distressed conditions as some other types of money market funds are, and the fund's board has no intention to impose a liquidity fee or redemption gate. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class M shares from year to year. The table shows the average annual total returns of the fund's Class M shares and Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Prior to May 1, 2016, the fund operated as a prime money market fund and invested in certain types of securities that the fund is no longer permitted to hold. Consequently, the performance information shown may have been different if the current investment limitations had been in effect during the period prior to the fund's conversion to a government money market fund.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q3, 2007: 1.29%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.41%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon Government Money Market Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	0.07%	0.02%	0.84%
Investor Shares	0.01%	none	0.76%

For the fund's current yield, Wealth Management Clients may call toll free 1-866-804-5023; Individual Clients may call toll free 1-800-DREYFUS (inside the U.S. only); BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services; participants in Qualified Employee Benefit Plans may call toll free 1-866-804-5023; and Institutional Investors and clients of Investment Advisory Firms may call toll free 1-866-804-5023.

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Value

Class M, Investor Prospectus | BNY Mellon Government Money Market Fund

Risk/Return:

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Risk/Return [Heading]

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Fund Summary - BNY Mellon Government Money Market Fund

Objective [Heading]

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Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The fund pursues its investment objective by investing only in government securities (i.e., securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, including those with floating or variable rates of interest), repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

The fund is a "government money market fund," as that term is defined in Rule 2a-7, and as such is required to invest at least 99.5% of its total assets in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in government securities and repurchase agreements collateralized solely by government securities (i.e., under normal circumstances, the fund will not invest more than 20% of its net assets in cash and/or repurchase agreements collateralized by cash). The securities in which the fund invests include those backed by the full faith and credit of the U.S. government, which include U.S. Treasury securities as well as securities issued by certain agencies of the U.S. government, and those that are neither insured nor guaranteed by the U.S. government.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund currently is not permitted to impose a fee upon the sale of shares (a "liquidity fee") or temporarily suspend redemptions (a redemption "gate") under distressed conditions as some other types of money market funds are, and the fund's board has no intention to impose a liquidity fee or redemption gate. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

Risk Money Market Fund [Text]

rr_RiskMoneyMarketFund

Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class M shares from year to year. The table shows the average annual total returns of the fund's Class M shares and Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Prior to May 1, 2016, the fund operated as a prime money market fund and invested in certain types of securities that the fund is no longer permitted to hold. Consequently, the performance information shown may have been different if the current investment limitations had been in effect during the period prior to the fund's conversion to a government money market fund.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2007: 1.29%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.41%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

0.41%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2007

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

1.29%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

none

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

For the fund's current yield, Wealth Management Clients may call toll free 1-866-804-5023; Individual Clients may call toll free 1-800-DREYFUS (inside the U.S. only); BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services; participants in Qualified Employee Benefit Plans may call toll free 1-866-804-5023; and Institutional Investors and clients of Investment Advisory Firms may call toll free 1-866-804-5023.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Money Market Seven Day Yield Phone

rr_MoneyMarketSevenDayYieldPhone

1-800-830-0549

Class M, Investor Prospectus | BNY Mellon Government Money Market Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.31%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 32

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

100

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

174

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

393

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

32

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

100

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

174

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 393

Annual Return 2007

rr_AnnualReturn2007

5.11%

Annual Return 2008

rr_AnnualReturn2008

2.80%

Annual Return 2009

rr_AnnualReturn2009

0.53%

Annual Return 2010

rr_AnnualReturn2010

0.05%

Annual Return 2011

rr_AnnualReturn2011

none

Annual Return 2012

rr_AnnualReturn2012

none

Annual Return 2013

rr_AnnualReturn2013

none

Annual Return 2014

rr_AnnualReturn2014

none

Annual Return 2015

rr_AnnualReturn2015

none

Annual Return 2016

rr_AnnualReturn2016

0.07%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.07%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.02%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.84%

Class M, Investor Prospectus | BNY Mellon Government Money Market Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.56%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 57

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

179

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

313

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

701

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

57

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

179

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

313

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 701

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.01%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

none

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.76%

XML

Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund

Fund Summary - BNY Mellon National Municipal Money Market Fund

Investment Objective

The fund seeks as high a level of current income exempt from federal income tax as is consistent with the preservation of capital and the maintenance of liquidity.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class M, Investor Prospectus - BNY Mellon National Municipal Money Market Fund	Class M Shares	Investor Shares
Investment advisory fees	0.15%	0.15%
Other Expenses - Shareholder services fees	none	0.25%
Other Expenses - Administration fees	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.04%	0.05%
Total annual fund operating expenses	0.31%	0.57%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class M, Investor Prospectus - BNY Mellon National Municipal Money Market Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	32	100	174	393
Investor Shares	58	183	318	714

Expense Example No Redemption - Class M, Investor Prospectus - BNY Mellon National Municipal Money Market Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class M Shares	32	100	174	393
Investor Shares	58	183	318	714

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets in short-term, high quality municipal obligations that provide income exempt from federal income tax. Among these are municipal notes, short-term municipal bonds, tax-exempt commercial paper and municipal leases.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund may impose a fee upon the sale of your shares (a "liquidity fee") or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of market conditions or other factors. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of a security, can cause the security's price to fall. Although the fund invests only in high quality debt securities, the credit quality of the securities held by the fund can change rapidly in certain market environments, and the default or a significant price decline of a single holding could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Liquidity fee and/or redemption gate risk. The fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of unusual market conditions, an unusually high volume of redemption requests, redemptions by a few large investors, or other reasons. If a liquidity fee is imposed by the fund, it would reduce the amount you will receive upon the redemption of your shares. A "gate" will suspend your ability to redeem your shares while the gate is imposed and may prevent the fund from being able to pay redemption proceeds within the allowable time period stated in this prospectus.

·Tax risk. To be tax-exempt, municipal obligations generally must meet certain regulatory requirements. If any such municipal obligation fails to meet these regulatory requirements, the interest received by the fund from its investment in such obligations and distributed to fund shareholders will be taxable.

·Municipal securities risk. Municipal securities may be fully or partially backed or enhanced by the taxing authority of a local government, by the current or anticipated revenues from a specific project or specific assets, or by the credit of, or liquidity enhancement provided by, a private issuer. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or the fund's ability to maintain a stable net asset value.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class M shares from year to year. The table shows the average annual total returns of the fund's Class M shares and Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Best Quarter
Q2, 2007: 0.87%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.36%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns - Class M, Investor Prospectus - BNY Mellon National Municipal Money Market Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class M Shares	0.17%	0.03%	0.57%
Investor Shares	0.05%	0.01%	0.49%

For the fund's current yield, Wealth Management Clients may call toll free 1-866-804-5023; Individual Clients may call toll free 1-800-DREYFUS (inside the U.S. only); BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services; participants in Qualified Employee Benefit Plans may call toll free 1-866-804-5023; and Institutional Investors and clients of Investment Advisory Firms may call toll free 1-866-804-5023.

XML

Label

Element

Value

Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon National Municipal Money Market Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of current income exempt from federal income tax as is consistent with the preservation of capital and the maintenance of liquidity.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets in short-term, high quality municipal obligations that provide income exempt from federal income tax. Among these are municipal notes, short-term municipal bonds, tax-exempt commercial paper and municipal leases.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund may impose a fee upon the sale of your shares (a "liquidity fee") or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of market conditions or other factors. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of a security, can cause the security's price to fall. Although the fund invests only in high quality debt securities, the credit quality of the securities held by the fund can change rapidly in certain market environments, and the default or a significant price decline of a single holding could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Liquidity fee and/or redemption gate risk. The fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of unusual market conditions, an unusually high volume of redemption requests, redemptions by a few large investors, or other reasons. If a liquidity fee is imposed by the fund, it would reduce the amount you will receive upon the redemption of your shares. A "gate" will suspend your ability to redeem your shares while the gate is imposed and may prevent the fund from being able to pay redemption proceeds within the allowable time period stated in this prospectus.

·Tax risk. To be tax-exempt, municipal obligations generally must meet certain regulatory requirements. If any such municipal obligation fails to meet these regulatory requirements, the interest received by the fund from its investment in such obligations and distributed to fund shareholders will be taxable.

·Municipal securities risk. Municipal securities may be fully or partially backed or enhanced by the taxing authority of a local government, by the current or anticipated revenues from a specific project or specific assets, or by the credit of, or liquidity enhancement provided by, a private issuer. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or the fund's ability to maintain a stable net asset value.

Risk Money Market Fund [Text]

rr_RiskMoneyMarketFund

Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class M shares from year to year. The table shows the average annual total returns of the fund's Class M shares and Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future. Performance for each share class will vary due to differences in expenses.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class M

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2007: 0.87%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Class M shares as of September 30, 2017 was 0.36%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class M shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

0.36%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2007

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

0.87%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

none

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

For the fund's current yield, Wealth Management Clients may call toll free 1-866-804-5023; Individual Clients may call toll free 1-800-DREYFUS (inside the U.S. only); BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services; participants in Qualified Employee Benefit Plans may call toll free 1-866-804-5023; and Institutional Investors and clients of Investment Advisory Firms may call toll free 1-866-804-5023.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Money Market Seven Day Yield Phone

rr_MoneyMarketSevenDayYieldPhone

1-800-830-0549

Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund | Class M Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.31%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 32

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

100

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

174

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

393

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

32

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

100

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

174

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 393

Annual Return 2007

rr_AnnualReturn2007

3.39%

Annual Return 2008

rr_AnnualReturn2008

1.93%

Annual Return 2009

rr_AnnualReturn2009

0.16%

Annual Return 2010

rr_AnnualReturn2010

0.06%

Annual Return 2011

rr_AnnualReturn2011

0.01%

Annual Return 2012

rr_AnnualReturn2012

none

Annual Return 2013

rr_AnnualReturn2013

none

Annual Return 2014

rr_AnnualReturn2014

none

Annual Return 2015

rr_AnnualReturn2015

none

Annual Return 2016

rr_AnnualReturn2016

0.17%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.17%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.03%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.57%

Class M, Investor Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.57%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 58

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

183

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

318

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

714

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

58

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

183

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

318

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 714

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.05%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.01%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.49%

XML

Investor Shares Prospectus | BNY Mellon Government Money Market Fund

Fund Summary - BNY Mellon Government Money Market Fund

Investment Objective

The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Investor Shares Prospectus BNY Mellon Government Money Market Fund Investor Shares
Investment advisory fees	0.15%
Other Expenses - Shareholder services fees	0.25%
Other Expenses - Administration fees	0.12%
Other Expenses - Other expenses of the fund	0.04%
Total annual fund operating expenses	0.56%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Investor Shares Prospectus | BNY Mellon Government Money Market Fund | Investor Shares | USD ($)	57	179	313	701

Expense Example No Redemption	1 Year	3 Years	5 Years	10 Years
Investor Shares Prospectus | BNY Mellon Government Money Market Fund | Investor Shares | USD ($)	57	179	313	701

Principal Investment Strategy

The fund pursues its investment objective by investing only in government securities (i.e., securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, including those with floating or variable rates of interest), repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

The fund is a "government money market fund," as that term is defined in Rule 2a-7, and as such is required to invest at least 99.5% of its total assets in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in government securities and repurchase agreements collateralized solely by government securities (i.e., under normal circumstances, the fund will not invest more than 20% of its net assets in cash and/or repurchase agreements collateralized by cash). The securities in which the fund invests include those backed by the full faith and credit of the U.S. government, which include U.S. Treasury securities as well as securities issued by certain agencies of the U.S. government, and those that are neither insured nor guaranteed by the U.S. government.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund currently is not permitted to impose a fee upon the sale of shares (a "liquidity fee") or temporarily suspend redemptions (a redemption "gate") under distressed conditions as some other types of money market funds are, and the fund's board has no intention to impose a liquidity fee or redemption gate. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Investor shares from year to year. The table shows the average annual total returns of the fund's Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Prior to May 1, 2016, the fund operated as a prime money market fund and invested in certain types of securities that the fund is no longer permitted to hold. Consequently, the performance information shown may have been different if the current investment limitations had been in effect during the period prior to the fund's conversion to a government money market fund.

Year-by-Year Total Returns as of 12/31 each year (%) Investor

Best Quarter
Q3, 2007: 1.22%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Investor shares as of September 30, 2017 was 0.22%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Investor Shares Prospectus | BNY Mellon Government Money Market Fund | Investor Shares	0.01%	none	0.76%

For the fund's current yield, BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services.

XML

Label

Element

Value

Investor Shares Prospectus | BNY Mellon Government Money Market Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Government Money Market Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The fund pursues its investment objective by investing only in government securities (i.e., securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, including those with floating or variable rates of interest), repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

The fund is a "government money market fund," as that term is defined in Rule 2a-7, and as such is required to invest at least 99.5% of its total assets in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, repurchase agreements collateralized solely by government securities and/or cash, and cash. The fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in government securities and repurchase agreements collateralized solely by government securities (i.e., under normal circumstances, the fund will not invest more than 20% of its net assets in cash and/or repurchase agreements collateralized by cash). The securities in which the fund invests include those backed by the full faith and credit of the U.S. government, which include U.S. Treasury securities as well as securities issued by certain agencies of the U.S. government, and those that are neither insured nor guaranteed by the U.S. government.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund currently is not permitted to impose a fee upon the sale of shares (a "liquidity fee") or temporarily suspend redemptions (a redemption "gate") under distressed conditions as some other types of money market funds are, and the fund's board has no intention to impose a liquidity fee or redemption gate. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Government securities risk. Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some cases there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security held by the fund does not apply to the market value of such security or to shares of the fund itself. A security backed by the U.S. Treasury or the full faith and credit of the United States is guaranteed only as to the timely payment of interest and principal when held to maturity.

·Repurchase agreement counterparty risk. The fund is subject to the risk that a counterparty in a repurchase agreement could fail to honor the terms of the agreement.

Risk Money Market Fund [Text]

rr_RiskMoneyMarketFund

Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Investor shares from year to year. The table shows the average annual total returns of the fund's Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Prior to May 1, 2016, the fund operated as a prime money market fund and invested in certain types of securities that the fund is no longer permitted to hold. Consequently, the performance information shown may have been different if the current investment limitations had been in effect during the period prior to the fund's conversion to a government money market fund.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Investor

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q3, 2007: 1.22%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Investor shares as of September 30, 2017 was 0.22%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Investor shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

0.22%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2007

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

1.22%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

none

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

For the fund's current yield, BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Money Market Seven Day Yield Phone

rr_MoneyMarketSevenDayYieldPhone

1-800-830-0549

Investor Shares Prospectus | BNY Mellon Government Money Market Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.56%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 57

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

179

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

313

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

701

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

57

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

179

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

313

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 701

Annual Return 2007

rr_AnnualReturn2007

4.85%

Annual Return 2008

rr_AnnualReturn2008

2.55%

Annual Return 2009

rr_AnnualReturn2009

0.33%

Annual Return 2010

rr_AnnualReturn2010

none

Annual Return 2011

rr_AnnualReturn2011

none

Annual Return 2012

rr_AnnualReturn2012

none

Annual Return 2013

rr_AnnualReturn2013

none

Annual Return 2014

rr_AnnualReturn2014

none

Annual Return 2015

rr_AnnualReturn2015

none

Annual Return 2016

rr_AnnualReturn2016

0.01%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.01%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

none

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.76%

XML

Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund

Fund Summary - BNY Mellon National Municipal Money Market Fund

Investment Objective

The fund seeks as high a level of current income exempt from federal income tax as is consistent with the preservation of capital and the maintenance of liquidity.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Investor Shares Prospectus BNY Mellon National Municipal Money Market Fund Investor Shares
Investment advisory fees	0.15%
Other Expenses - Shareholder services fees	0.25%
Other Expenses - Administration fees	0.12%
Other Expenses - Other expenses of the fund	0.05%
Total annual fund operating expenses	0.57%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares | USD ($)	58	183	318	714

Expense Example No Redemption	1 Year	3 Years	5 Years	10 Years
Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares | USD ($)	58	183	318	714

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets in short-term, high quality municipal obligations that provide income exempt from federal income tax. Among these are municipal notes, short-term municipal bonds, tax-exempt commercial paper and municipal leases.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund may impose a fee upon the sale of your shares (a "liquidity fee") or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of market conditions or other factors. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of a security, can cause the security's price to fall. Although the fund invests only in high quality debt securities, the credit quality of the securities held by the fund can change rapidly in certain market environments, and the default or a significant price decline of a single holding could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Liquidity fee and/or redemption gate risk. The fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of unusual market conditions, an unusually high volume of redemption requests, redemptions by a few large investors, or other reasons. If a liquidity fee is imposed by the fund, it would reduce the amount you will receive upon the redemption of your shares. A "gate" will suspend your ability to redeem your shares while the gate is imposed and may prevent the fund from being able to pay redemption proceeds within the allowable time period stated in this prospectus.

·Tax risk. To be tax-exempt, municipal obligations generally must meet certain regulatory requirements. If any such municipal obligation fails to meet these regulatory requirements, the interest received by the fund from its investment in such obligations and distributed to fund shareholders will be taxable.

·Municipal securities risk. Municipal securities may be fully or partially backed or enhanced by the taxing authority of a local government, by the current or anticipated revenues from a specific project or specific assets, or by the credit of, or liquidity enhancement provided by, a private issuer. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or the fund's ability to maintain a stable net asset value.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Investor shares from year to year. The table shows the average annual total returns of the fund's Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Year-by-Year Total Returns as of 12/31 each year (%) Investor

Best Quarter
Q2, 2007: 0.81%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Investor shares as of September 30, 2017 was 0.18%.

Average Annual Total Returns as of 12/31/16

Average Annual Returns	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares	0.05%	0.01%	0.49%

For the fund's current yield, BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services.

XML

Label

Element

Value

Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon National Municipal Money Market Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks as high a level of current income exempt from federal income tax as is consistent with the preservation of capital and the maintenance of liquidity.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then hold or redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets in short-term, high quality municipal obligations that provide income exempt from federal income tax. Among these are municipal notes, short-term municipal bonds, tax-exempt commercial paper and municipal leases.

Although the fund seeks to provide income exempt from federal income tax, income from some of the fund's holdings may be subject to the federal alternative minimum tax.

The fund is a money market fund subject to the maturity, quality, liquidity and diversification requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended, and seeks to maintain a stable share price of $1.00.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund's yield will fluctuate as the short-term securities in its portfolio mature or are sold and the proceeds are reinvested in securities with different interest rates. The fund may impose a fee upon the sale of your shares (a "liquidity fee") or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of market conditions or other factors. Neither the investment adviser nor its affiliates have a legal obligation to provide financial support to the fund, and you should not expect that the investment adviser or its affiliates will provide financial support to the fund at any time. The following are the principal risks that could reduce the fund's income level and/or share price:

·Interest rate risk. This risk refers to the decline in the prices of fixed-income securities that may accompany a rise in the overall level of interest rates. A sharp and unexpected rise in interest rates could impair the fund's ability to maintain a stable net asset value. A low interest rate environment may prevent the fund from providing a positive yield or paying fund expenses out of fund assets and could impair the fund's ability to maintain a stable net asset value.

·Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of a security, can cause the security's price to fall. Although the fund invests only in high quality debt securities, the credit quality of the securities held by the fund can change rapidly in certain market environments, and the default or a significant price decline of a single holding could impair the fund's ability to maintain a stable net asset value.

·Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities may fall dramatically, potentially impairing the fund's ability to maintain a stable net asset value, even during periods of declining interest rates.

·Liquidity fee and/or redemption gate risk. The fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares (a redemption "gate") if the fund's liquidity falls below required minimums because of unusual market conditions, an unusually high volume of redemption requests, redemptions by a few large investors, or other reasons. If a liquidity fee is imposed by the fund, it would reduce the amount you will receive upon the redemption of your shares. A "gate" will suspend your ability to redeem your shares while the gate is imposed and may prevent the fund from being able to pay redemption proceeds within the allowable time period stated in this prospectus.

·Tax risk. To be tax-exempt, municipal obligations generally must meet certain regulatory requirements. If any such municipal obligation fails to meet these regulatory requirements, the interest received by the fund from its investment in such obligations and distributed to fund shareholders will be taxable.

·Municipal securities risk. Municipal securities may be fully or partially backed or enhanced by the taxing authority of a local government, by the current or anticipated revenues from a specific project or specific assets, or by the credit of, or liquidity enhancement provided by, a private issuer. Special factors, such as legislative changes, and state and local economic and business developments, may adversely affect the yield and/or the fund's ability to maintain a stable net asset value.

Risk Money Market Fund [Text]

rr_RiskMoneyMarketFund

Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Investor shares from year to year. The table shows the average annual total returns of the fund's Investor shares over time. The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Investor

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2007: 0.81%
Worst Quarter
Q3, 2015: 0.00%

The year-to-date total return of the fund's Investor shares as of September 30, 2017 was 0.18%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Investor shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

0.18%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2007

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

0.81%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

none

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

For the fund's current yield, BNY Mellon Wealth Brokerage Clients may call toll free 1-800-830-0549 — Option 2 for BNY Mellon Wealth Management Direct or 1-800-843-5466 for former brokerage clients of BNY Mellon Wealth Advisors whose accounts are now held by Dreyfus Brokerage Services.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns as of 12/31/16

Money Market Seven Day Yield Phone

rr_MoneyMarketSevenDayYieldPhone

1-800-830-0549

Investor Shares Prospectus | BNY Mellon National Municipal Money Market Fund | Investor Shares

Risk/Return:

rr_RiskReturnAbstract

Investment advisory fees

rr_ManagementFeesOverAssets

0.15%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.57%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 58

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

183

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

318

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

714

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

58

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

183

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

318

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 714

Annual Return 2007

rr_AnnualReturn2007

3.14%

Annual Return 2008

rr_AnnualReturn2008

1.67%

Annual Return 2009

rr_AnnualReturn2009

0.04%

Annual Return 2010

rr_AnnualReturn2010

none

Annual Return 2011

rr_AnnualReturn2011

none

Annual Return 2012

rr_AnnualReturn2012

none

Annual Return 2013

rr_AnnualReturn2013

none

Annual Return 2014

rr_AnnualReturn2014

none

Annual Return 2015

rr_AnnualReturn2015

none

Annual Return 2016

rr_AnnualReturn2016

0.05%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

0.05%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.01%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.49%

XML

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund

Fund Summary - BNY Mellon Income Stock Fund

Investment Objective

The fund seeks total return (consisting of capital appreciation and income).

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or shares of other funds in the Dreyfus Family of Funds that are subject to a sales charge. More information about sales charges, including these and other discounts and waivers, is available from your financial professional and in the Shareholder Guide section beginning on page 12 of the prospectus and in the How to Buy Shares section beginning on page III-1 of the fund's Statement of Additional Information.

Shareholder Fees - Class A, C, I, Y Prospectus - BNY Mellon Income Stock Fund	Class A		Class C	Class I	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%		none	none	none
Maximum deferred sales charge (load) (as a percentage of lower of purchase or sale price)	none	[1]	1.00%	none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Class A, C, I, Y Prospectus - BNY Mellon Income Stock Fund	Class A	Class C	Class I	Class Y
Investment advisory fees	0.65%	0.65%	0.65%	0.65%
Distribution (12b-1) fees	none	0.75%	none	none
Other Expenses - Shareholder services fees	0.25%	0.25%	none	none
Other Expenses - Administration fees	0.12%	0.12%	0.12%	0.12%
Other Expenses - Other expenses of the fund	0.09%	0.08%	0.08%	0.04%
Total annual fund operating expenses	1.11%	1.85%	0.85%	0.81%

Example

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example - Class A, C, I, Y Prospectus - BNY Mellon Income Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class A	682	908	1,151	1,849
Class C	288	582	1,001	2,169
Class I	87	271	471	1,049
Class Y	83	259	450	1,002

You would pay the following expenses if you did not redeem your shares:

Expense Example No Redemption - Class A, C, I, Y Prospectus - BNY Mellon Income Stock Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class A	682	908	1,151	1,849
Class C	188	582	1,001	2,169
Class I	87	271	471	1,049
Class Y	83	259	450	1,002

Portfolio Turnover

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52.66% of the average value of its portfolio.

Principal Investment Strategy

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks. The fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The investment adviser chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies. The fund's investment process is designed to provide investors with investment exposure to sector weightings and risk characteristics generally similar to those of the Dow Jones U.S. Select Dividend^TM Index (Dow Jones Index), but allocations may differ from those of the Dow Jones Index. The fund invests primarily in common stocks but also may invest up to 10% of its assets in convertible securities and up to 10% of its assets in preferred stocks.

Principal Risks

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Convertible securities risk. Convertible securities may be converted at either a stated price or stated rate into underlying shares of common stock. Convertible securities generally are subordinated to other similar but non-convertible securities of the same issuer. Although to a lesser extent than with fixed-income securities, the market value of convertible securities tends to decline as interest rates increase. In addition, because of the conversion feature, the market value of convertible securities tends to vary with fluctuations in the market value of the underlying common stock. Although convertible securities provide for a stable stream of income, they are subject to the risk that their issuers may default on their obligations. Convertible securities also offer the potential for capital appreciation through the conversion feature, although there can be no assurance of capital appreciation because securities prices fluctuate. Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality because of the potential for capital appreciation.

·Preferred stock risk. Preferred stock is a class of a capital stock that typically pays dividends at a specified rate. Preferred stock is generally senior to common stock, but subordinate to debt securities, with respect to the payment of dividends and on liquidation of the issuer. The market value of preferred stock generally decreases when interest rates rise and is also affected by the issuer's ability to make payments on the preferred stock.

Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class A shares from year to year. Sales charges, if any, are not reflected in the bar chart, and if those charges were included, returns would have been less than those shown. The table compares the average annual total returns of the fund's Class A, Class C, Class I and Class Y shares to those of the Dow Jones Index. The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. More recent performance information may be available at www.dreyfus.com.

Periods prior to May 31, 2016, the inception date for Class A, Class C, Class I and Class Y shares, reflect the performance of the fund's Class M shares, which are offered in a separate prospectus, adjusted in the table to reflect applicable sales charges. Such performance figures have not been adjusted to reflect applicable class fees and expenses; if these expenses had been reflected, the performance shown for Class A, Class C and Class I shares would have been lower. Each share class is invested in the same portfolio of securities, and the annual returns would have differed only to the extent that the classes do not have the same expenses.

After-tax performance is shown only for Class A shares. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. After-tax performance of the fund's other share classes will vary. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

Year-by-Year Total Returns as of 12/31 each year (%) Class A

Best Quarter
Q2, 2009: 17.95%
Worst Quarter
Q4, 2008: -19.85%

The year-to-date total return of the fund's Class A shares as of September 30, 2017 was 7.86%.

Average Annual Total Returns (as of 12/31/16)

Average Annual Returns - Class A, C, I, Y Prospectus - BNY Mellon Income Stock Fund	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Class A	10.03%	13.57%	6.20%
Class C	15.28%	14.83%	6.79%
Class I	17.03%	14.98%	6.85%
Class Y	16.90%	14.95%	6.84%
After Taxes on Distributions | Class A	8.63%	11.36%	4.52%
After Taxes on Distributions and Sale of Fund Shares | Class A	6.73%	10.41%	4.68%
Dow Jones Index reflects no deductions for fees, expenses or taxes	21.98%	14.64%	6.72%

[1] Class A shares bought without an initial sales charge as part of an investment of $1 million or more may be charged a deferred sales charge of 1.00% if redeemed within one year.

XML

Label

Element

Value

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

Fund Summary - BNY Mellon Income Stock Fund

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total return (consisting of capital appreciation and income).

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or shares of other funds in the Dreyfus Family of Funds that are subject to a sales charge. More information about sales charges, including these and other discounts and waivers, is available from your financial professional and in the Shareholder Guide section beginning on page 12 of the prospectus and in the How to Buy Shares section beginning on page III-1 of the fund's Statement of Additional Information.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52.66% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

52.66%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or shares of other funds in the Dreyfus Family of Funds that are subject to a sales charge.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

You would pay the following expenses if you did not redeem your shares:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategy

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in stocks. The fund seeks to focus on dividend-paying stocks and other investments and investment techniques that provide income. The investment adviser chooses stocks through a disciplined investment process that combines computer modeling techniques, fundamental analysis and risk management. The fund emphasizes those stocks with value characteristics, although it may also purchase growth stocks. The fund may invest in the stocks of companies of any size, although it focuses on large-cap companies. The fund's investment process is designed to provide investors with investment exposure to sector weightings and risk characteristics generally similar to those of the Dow Jones U.S. Select Dividend^TM Index (Dow Jones Index), but allocations may differ from those of the Dow Jones Index. The fund invests primarily in common stocks but also may invest up to 10% of its assets in convertible securities and up to 10% of its assets in preferred stocks.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

·Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company's industry.

·Market sector risk. The fund may significantly overweight or underweight certain companies, industries or market sectors, which may cause the fund's performance to be more or less sensitive to developments affecting those companies, industries or sectors.

·Large-cap stock risk. To the extent the fund invests in large capitalization stocks, the fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor.

·Growth and value stock risk. By investing in a mix of growth and value companies, the fund assumes the risks of both. Investors often expect growth companies to increase their earnings at a certain rate. If these expectations are not met, investors can punish the stocks inordinately, even if earnings do increase. In addition, growth stocks may lack the dividend yield that may cushion stock prices in market downturns. Value stocks involve the risk that they may never reach their expected full market value, either because the market fails to recognize the stock's intrinsic worth or the expected value was misgauged. They also may decline in price even though in theory they are already undervalued.

·Convertible securities risk. Convertible securities may be converted at either a stated price or stated rate into underlying shares of common stock. Convertible securities generally are subordinated to other similar but non-convertible securities of the same issuer. Although to a lesser extent than with fixed-income securities, the market value of convertible securities tends to decline as interest rates increase. In addition, because of the conversion feature, the market value of convertible securities tends to vary with fluctuations in the market value of the underlying common stock. Although convertible securities provide for a stable stream of income, they are subject to the risk that their issuers may default on their obligations. Convertible securities also offer the potential for capital appreciation through the conversion feature, although there can be no assurance of capital appreciation because securities prices fluctuate. Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality because of the potential for capital appreciation.

·Preferred stock risk. Preferred stock is a class of a capital stock that typically pays dividends at a specified rate. Preferred stock is generally senior to common stock, but subordinate to debt securities, with respect to the payment of dividends and on liquidation of the issuer. The market value of preferred stock generally decreases when interest rates rise and is also affected by the issuer's ability to make payments on the preferred stock.

Risk Lose Money [Text]

rr_RiskLoseMoney

The fund's share price fluctuates, sometimes dramatically, which means you could lose money.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the performance of the fund's Class A shares from year to year. Sales charges, if any, are not reflected in the bar chart, and if those charges were included, returns would have been less than those shown. The table compares the average annual total returns of the fund's Class A, Class C, Class I and Class Y shares to those of the Dow Jones Index. The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. More recent performance information may be available at www.dreyfus.com.

Periods prior to May 31, 2016, the inception date for Class A, Class C, Class I and Class Y shares, reflect the performance of the fund's Class M shares, which are offered in a separate prospectus, adjusted in the table to reflect applicable sales charges. Such performance figures have not been adjusted to reflect applicable class fees and expenses; if these expenses had been reflected, the performance shown for Class A, Class C and Class I shares would have been lower. Each share class is invested in the same portfolio of securities, and the annual returns would have differed only to the extent that the classes do not have the same expenses.

After-tax performance is shown only for Class A shares. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. After-tax performance of the fund's other share classes will vary. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts. Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.dreyfus.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-Year Total Returns as of 12/31 each year (%) Class A

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges, if any, are not reflected in the bar chart, and if those charges were included, returns would have been less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter
Q2, 2009: 17.95%
Worst Quarter
Q4, 2008: -19.85%

The year-to-date total return of the fund's Class A shares as of September 30, 2017 was 7.86%.

Year to Date Return, Label

rr_YearToDateReturnLabel

The year-to-date total return of the fund's Class A shares

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

7.86%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.95%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.85%)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

reflects no deductions for fees, expenses or taxes

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through U.S. tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax performance is shown only for Class A shares.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

Returns on taxes after distributions and sale of fund shares may be higher than returns before taxes or returns after taxes on distributions due to an assumed tax benefit from losses on a sale of the fund's shares at the end of the period.

Caption

rr_AverageAnnualReturnCaption

Average Annual Total Returns (as of 12/31/16)

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Dow Jones Index reflects no deductions for fees, expenses or taxes

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

21.98%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.64%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.72%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

Maximum deferred sales charge (load) (as a percentage of lower of purchase or sale price)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Distribution (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.09%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.11%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A shares bought without an initial sales charge as part of an investment of $1 million or more may be charged a deferred sales charge of 1.00% if redeemed within one year.

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 682

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

908

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,151

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,849

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

682

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

908

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,151

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,849

Annual Return 2007

rr_AnnualReturn2007

3.58%

Annual Return 2008

rr_AnnualReturn2008

(36.02%)

Annual Return 2009

rr_AnnualReturn2009

23.07%

Annual Return 2010

rr_AnnualReturn2010

14.27%

Annual Return 2011

rr_AnnualReturn2011

3.61%

Annual Return 2012

rr_AnnualReturn2012

14.86%

Annual Return 2013

rr_AnnualReturn2013

34.24%

Annual Return 2014

rr_AnnualReturn2014

10.64%

Annual Return 2015

rr_AnnualReturn2015

0.66%

Annual Return 2016

rr_AnnualReturn2016

16.73%

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.03%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

13.57%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.20%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class A | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.63%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

11.36%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.52%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class A | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

6.73%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

10.41%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.68%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of lower of purchase or sale price)

rr_MaximumDeferredSalesChargeOverOther

1.00%

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Distribution (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.75%

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

0.25%

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.85%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 288

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

582

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,001

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,169

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

188

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

582

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,001

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,169

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

15.28%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.83%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.79%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of lower of purchase or sale price)

rr_MaximumDeferredSalesChargeOverOther

none

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Distribution (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.08%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.85%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 87

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

271

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

471

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,049

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

87

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

271

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

471

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,049

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

17.03%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.98%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.85%

Class A, C, I, Y Prospectus | BNY Mellon Income Stock Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of lower of purchase or sale price)

rr_MaximumDeferredSalesChargeOverOther

none

Investment advisory fees

rr_ManagementFeesOverAssets

0.65%

Distribution (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses - Shareholder services fees

rr_Component1OtherExpensesOverAssets

none

Other Expenses - Administration fees

rr_Component2OtherExpensesOverAssets

0.12%

Other Expenses - Other expenses of the fund

rr_Component3OtherExpensesOverAssets

0.04%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.81%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 83

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

259

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

450

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,002

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

83

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

259

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

450

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,002

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

16.90%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

14.95%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

6.84%

[1] Class A shares bought without an initial sales charge as part of an investment of $1 million or more may be charged a deferred sales charge of 1.00% if redeemed within one year.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Dec. 29, 2017