Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Oct. 01, 2012
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
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. 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 certain funds in the Dreyfus Family of Funds. More information about these and other discounts is available from your financial professional and in the Shareholder Guide section on page 9 of the Prospectus and in the How to Buy Shares section and the Additional Information About How to Buy Shares section on page II-1 and page III-1, respectively, of the fund's Statement of Additional Information. 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% if redeemed within one year.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as 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 45.73% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	45.73%
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 certain funds in the Dreyfus Family of Funds.
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 the stocks of companies organized, or with a majority of assets or business, in emerging market countries. In selecting stocks, the portfolio managers identify potential investments through extensive quantitative and fundamental research using a value-oriented, research-driven approach. Emphasizing individual stock selection rather than economic and industry trends, the fund focuses on value, business health and business momentum.
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. o Foreign investment risk. The fund's performance may 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. To the extent the fund's investments are concentrated in a limited number of foreign countries, the fund's performance could be more volatile than that of more geographically diversified funds. o Emerging market risk. The securities of issuers located in emerging markets tend to be more volatile and less liquid than securities of issuers located in more mature economies, and emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. The securities of issuers located or doing substantial business in emerging markets are often subject to rapid and large changes in price. o 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. o 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 weakness in the stock market or because of factors that affect the company or its particular industry. o Liquidity risk. When there is little or no active trading market for a security, the fund may not be able to sell the security in a timely manner at its perceived value, which could cause the fund's share price to fall. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities. o 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 table compares the average annual total returns of the fund's shares to those of a broad measure of market performance. The fund's past performance (before and after taxes) is no guarantee of future results. More recent performance information may be available at www.dreyfus.com.
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 no guarantee of future results.
Bar Chart [Heading]	rr_BarChartHeading	Year-by-Year Total Returns as of 12/31 each year (%) -- Class A
Bar Chart Narrative [Text Block]	rr_BarChartNarrativeTextBlock	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.
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: 36.58%                      Worst Quarter                         Q4, 2008: -25.48%                                                                                                      The year-to-date total return of the fund's Class A shares as of 6/30/12 was     2.55%.
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 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. After-tax performance of the fund's other share classes will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax performance is shown only for Class A shares. After-tax performance of the fund's other share classes 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 tax-deferred arrangements such as 401(k) plans or individual retirement accounts. The performance figures for the fund's Class C and I shares for periods prior to 11/15/02 reflect the performance of the fund's Class A shares adjusted to reflect each share class' applicable sales charge. Such performance figures have not been adjusted, however, to reflect applicable class fees and expenses; if such fees and expenses had been reflected, the performance shown for Class C shares for such periods may have been lower.
Caption	rr_AverageAnnualReturnCaption	Average Annual Total Returns (as of 12/31/11)
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | MSCI Emerging Markets Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	MSCI Emerging Markets Index reflects no deduction for fees, expenses or taxes
1 Year	rr_AverageAnnualReturnYear01	(18.42%)
5 Years	rr_AverageAnnualReturnYear05	2.40%
10 Years	rr_AverageAnnualReturnYear10	13.86%
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | Class A
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.75%
Maximum contingent deferred sales charge (load) (as a percentage of lower of purchase or sale price)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum redemption fee (as a percentage of transaction amount, charged only when selling shares you have owned for less than 60 days)	rr_RedemptionFee	(2.00)
Management fees	rr_ManagementFeesOverAssets	1.25%
Distribution (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses (including shareholder services fees)	rr_OtherExpensesOverAssets	0.53%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.78%	[1]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	745
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	1,103
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,484
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,549
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	745
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	1,103
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,484
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,549
Annual Return 2002	rr_AnnualReturn2002	(1.36%)
Annual Return 2003	rr_AnnualReturn2003	52.54%
Annual Return 2004	rr_AnnualReturn2004	26.88%
Annual Return 2005	rr_AnnualReturn2005	25.42%
Annual Return 2006	rr_AnnualReturn2006	27.18%
Annual Return 2007	rr_AnnualReturn2007	27.23%
Annual Return 2008	rr_AnnualReturn2008	(47.09%)
Annual Return 2009	rr_AnnualReturn2009	75.46%
Annual Return 2010	rr_AnnualReturn2010	15.39%
Annual Return 2011	rr_AnnualReturn2011	(24.14%)
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date total return
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Jun. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	2.55%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	36.58%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(25.48%)
Label	rr_AverageAnnualReturnLabel	Class A returns before taxes
1 Year	rr_AverageAnnualReturnYear01	(28.49%)
5 Years	rr_AverageAnnualReturnYear05	(0.52%)
10 Years	rr_AverageAnnualReturnYear10	11.49%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 28, 1996
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | Class A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A returns after taxes on distributions
1 Year	rr_AverageAnnualReturnYear01	(29.54%)
5 Years	rr_AverageAnnualReturnYear05	(2.79%)
10 Years	rr_AverageAnnualReturnYear10	9.47%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 28, 1996
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | Class A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Class A returns after taxes on distributions and sale of fund shares
1 Year	rr_AverageAnnualReturnYear01	(16.65%)
5 Years	rr_AverageAnnualReturnYear05	(0.62%)
10 Years	rr_AverageAnnualReturnYear10	10.11%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 28, 1996
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | Class C
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum contingent deferred sales charge (load) (as a percentage of lower of purchase or sale price)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%
Maximum redemption fee (as a percentage of transaction amount, charged only when selling shares you have owned for less than 60 days)	rr_RedemptionFee	(2.00)
Management fees	rr_ManagementFeesOverAssets	1.25%
Distribution (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.75%
Other expenses (including shareholder services fees)	rr_OtherExpensesOverAssets	0.57%
Total annual fund operating expenses	rr_ExpensesOverAssets	2.57%	[1]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	360
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	799
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,365
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,905
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	260
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	799
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,365
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,905
Label	rr_AverageAnnualReturnLabel	Class C returns before taxes
1 Year	rr_AverageAnnualReturnYear01	(25.46%)
5 Years	rr_AverageAnnualReturnYear05	(0.13%)
10 Years	rr_AverageAnnualReturnYear10	11.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 15, 2002
Dreyfus Emerging Markets Fund (Prospectus Summary) | Dreyfus Emerging Markets Fund | Class I
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum contingent deferred sales charge (load) (as a percentage of lower of purchase or sale price)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum redemption fee (as a percentage of transaction amount, charged only when selling shares you have owned for less than 60 days)	rr_RedemptionFee	(2.00)
Management fees	rr_ManagementFeesOverAssets	1.25%
Distribution (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses (including shareholder services fees)	rr_OtherExpensesOverAssets	0.31%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.56%	[1]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	159
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	493
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	850
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,856
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	159
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	493
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	850
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,856
Label	rr_AverageAnnualReturnLabel	Class I returns before taxes
1 Year	rr_AverageAnnualReturnYear01	(24.06%)
5 Years	rr_AverageAnnualReturnYear05	0.84%
10 Years	rr_AverageAnnualReturnYear10	12.41%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 15, 2002

[1] The Dreyfus Corporation has agreed to waive receipt of a portion of the fund's management fee in the amount of .10 of 1% of the value of the fund's average daily total assets until March 31, 2013.