Label	Element	Value
Prospectus [Line Items]	rr_ProspectusLineItems
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Dec. 31, 2018
Entity Registrant Name	dei_EntityRegistrantName	PUTNAM FUNDS TRUST
Entity Central Index Key	dei_EntityCentralIndexKey	0001005942
Amendment Flag	dei_AmendmentFlag	false
Entity Inv Company Type	dei_EntityInvCompanyType	N-1A
Trading Symbol	dei_TradingSymbol	PFT
Document Creation Date	dei_DocumentCreationDate	Sep. 26, 2019
Document Effective Date	dei_DocumentEffectiveDate	Sep. 30, 2019
Prospectus Date	rr_ProspectusDate	Sep. 30, 2019
Putnam Dynamic Asset Allocation Equity Fund
Prospectus [Line Items]	rr_ProspectusLineItems
Risk/Return [Heading]	rr_RiskReturnHeading	Fund summary
Objective [Heading]	rr_ObjectiveHeading	Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Putnam Dynamic Asset Allocation Equity Fund seeks long-term growth.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses 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 Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 14 of the fund’s prospectus, in the Appendix to the fund’s prospectus, and in How to buy shares beginning on page II-1 of the fund’s statement of additional information (SAI).
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 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-related costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund’s shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund’s turnover rate in the most recent fiscal year was 115%.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	115.00%
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 Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 14 of the fund's prospectus, in the Appendix to the fund's prospectus, and in How to buy shares beginning on page II-1 of the fund's statement of additional information (SAI).
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then, except as indicated, redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund’s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Investments, risks, and performance
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Investments We invest mainly in common stocks (growth or value stocks or both) of large and midsize companies worldwide. Under normal circumstances, we invest at least 80% of the fund’s net assets in common stocks. This policy may be changed only after 60 days’ notice to shareholders. While we typically allocate approximately 75% of the fund’s assets to investments in U.S. companies, and 25% of the fund’s assets to investments in international companies, these allocations may vary. We invest mainly in developed countries, but may invest in emerging markets. We may consider, among other factors, a company’s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also consider other factors that we believe will cause the stock price to rise. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes.
Risk [Heading]	rr_RiskHeading	Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	It is important to understand that you can lose money by investing in the fund. If the quantitative models or data that are used in managing the fund prove to be incorrect or incomplete, investment decisions made in reliance on the models or data may not produce the desired results and the fund may realize losses. The value of investments in the fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, and factors related to a specific issuer, geography, industry or sector. These and other factors may lead to increased volatility and reduced liquidity in the fund’s portfolio holdings. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. These risks are generally greater for small and midsize companies. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments, particularly investments in emerging markets, may carry risks associated with potentially less stable economies or governments (such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation), and may be or become illiquid. Our use of derivatives may increase the risk of investing in the fund by increasing investment exposure (which may be considered leverage) or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions and the potential failure of the other party to the instrument to meet its obligations. The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investor profile The fund serves as an underlying equity investment of other funds that allocate their portfolios among the Putnam funds to obtain varying exposures to equity and fixed-income investments. The fund also is designed for investors seeking long-term growth and who are willing to wait out short-term market fluctuations.
Risk Lose Money [Text]	rr_RiskLoseMoney	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	putnam.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Please remember that past performance is not necessarily an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Annual total returns for class A shares before sales charges
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart does not reflect the impact of sales charges. If it did, performance would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Year-to-date performance through 6/30/19  15.29% Best calendar quarter Q1 2012   13.55% Worst calendar quarter Q3 2011 −18.48%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date performance
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Jun. 30, 2019
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	15.29%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best calendar quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Mar. 31, 2012
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	13.55%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst calendar quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(18.48%)
Performance Table Heading	rr_PerformanceTableHeading	Average annual total returns after sales charges (for periods ended 12/31/18)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for class A shares only and will vary for other classes.
Performance Table Footnotes	rr_PerformanceTableFootnotesTextBlock	The Putnam Equity Blended Index is an unmanaged index administered by Putnam Management, 75% of which is the Russell 3000 Index, 19% of which is the MSCI EAFE Index (ND), and 6% of which is the MSCI Emerging Markets Index (GD).
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement.
Putnam Dynamic Asset Allocation Equity Fund | Russell 3000 Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(5.24%)	[1]
5 Years	rr_AverageAnnualReturnYear05	7.91%	[1]
Since Inception	rr_AverageAnnualReturnSinceInception	14.26%	[1]
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009	[1]
Putnam Dynamic Asset Allocation Equity Fund | Putnam Equity Blended Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(7.39%)
5 Years	rr_AverageAnnualReturnYear05	6.20%
Since Inception	rr_AverageAnnualReturnSinceInception	12.80%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009
Putnam Dynamic Asset Allocation Equity Fund | Class A
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[2]
Management fees	rr_ManagementFeesOverAssets	0.59%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none	[3]
Other expenses	rr_OtherExpensesOverAssets	0.56%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.15%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.28%)	[4]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 659
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	893
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,146
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,869
Annual Return 2010	rr_AnnualReturn2010	15.03%
Annual Return 2011	rr_AnnualReturn2011	(4.49%)
Annual Return 2012	rr_AnnualReturn2012	17.40%
Annual Return 2013	rr_AnnualReturn2013	30.63%
Annual Return 2014	rr_AnnualReturn2014	10.18%
Annual Return 2015	rr_AnnualReturn2015	(0.21%)
Annual Return 2016	rr_AnnualReturn2016	7.50%
Annual Return 2017	rr_AnnualReturn2017	22.71%
Annual Return 2018	rr_AnnualReturn2018	(10.07%)
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(15.24%)
5 Years	rr_AverageAnnualReturnYear05	4.21%
Since Inception	rr_AverageAnnualReturnSinceInception	11.63%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009
Putnam Dynamic Asset Allocation Equity Fund | Class A | after taxes on distributions
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(18.36%)
5 Years	rr_AverageAnnualReturnYear05	1.60%
Since Inception	rr_AverageAnnualReturnSinceInception	8.49%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009
Putnam Dynamic Asset Allocation Equity Fund | Class A | after taxes on distributions and sale of fund shares
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(7.46%)
5 Years	rr_AverageAnnualReturnYear05	2.74%
Since Inception	rr_AverageAnnualReturnSinceInception	8.66%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009
Putnam Dynamic Asset Allocation Equity Fund | Class P
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.59%
Other expenses	rr_OtherExpensesOverAssets	0.32%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.91%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.28%)	[4]
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 64
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	262
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	476
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,094
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(9.81%)	[5]
5 Years	rr_AverageAnnualReturnYear05	5.59%	[5]
Since Inception	rr_AverageAnnualReturnSinceInception	12.37%	[5]
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 23, 2009	[5]
Putnam Dynamic Risk Allocation Fund
Prospectus [Line Items]	rr_ProspectusLineItems
Risk/Return [Heading]	rr_RiskReturnHeading	Fund summary
Objective [Heading]	rr_ObjectiveHeading	Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Putnam Dynamic Risk Allocation Fund seeks total return. Total return is composed of capital appreciation and income.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses 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 Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 20 of the fund’s prospectus, in the Appendix to the fund’s prospectus, and in How to buy shares beginning on page II-1 of the fund’s statement of additional information (SAI).
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 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-related costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund’s shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund’s turnover rate in the most recent fiscal year was 255%.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	255.00%
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 Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 20 of the fund's prospectus, in the Appendix to the fund's prospectus, and in How to buy shares beginning on page II-1 of the fund's statement of additional information (SAI).
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then, except as indicated, redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund’s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Investments, risks, and performance
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Investments The fund invests in a diversified set of asset classes. By investing in a broader set of asset classes than a traditional balanced fund, and by using leverage to increase the fund’s exposures to asset classes, we believe that the fund may achieve a higher total return than a traditional balanced fund with approximately the same amount of risk as a traditional balanced fund. Risk is measured by the volatility of the fund’s investment portfolio. The fund may invest without limit in U.S., international, and emerging markets equity securities (growth or value stocks or both) of companies of any size and fixed-income securities (including in below-investment-grade securities, which are sometimes referred to as “junk bonds”); mortgage- and asset-backed securities; inflation-protected securities; commodities; and real estate investment trusts (REITs). These asset classes offer different return potential and exposure to different investment risks. We allocate the fund’s assets among asset classes in a manner intended to diversify the fund’s exposure to these different types of risk. We typically use leverage to adjust or to increase the fund’s exposure to certain asset classes in order to diversify, or balance, risk exposure. We expect that, on average, net notional investment exposure of approximately 150% of the net assets of the fund will result from the fund’s allocation strategy under normal market conditions, although the amounts of leverage may be significantly higher or lower at any given time. We believe that better risk diversification creates the potential for the fund to perform well in a variety of market environments. Because the potential risks and returns of asset classes, the costs of leverage, and the benefits of diversification vary over time and with market conditions, we make dynamic adjustments to the fund’s asset allocations as the market environment changes. We use qualitative analysis, which includes evaluation of the business cycle environment and its impact on different asset classes, and quantitative techniques, which incorporate individual valuation and relative valuation measures, to establish asset class allocations that we believe will enable the fund to perform well in a variety of environments. We also use active trading strategies, such as active security selection, tactical asset allocation, currency transactions and options transactions. Certain of these strategies may introduce additional investment leverage. When making particular investments within an asset class, we may consider, among other factors, a company’s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell equity investments, and, among other factors, credit, interest rate and prepayment risks when deciding whether to buy or sell fixed-income investments. We may also take into account general market conditions when making investment decisions. We typically use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, to a significant extent for hedging purposes, to obtain leverage, and to adjust the return and volatility characteristics of the fund’s investments. We may also engage in short sales of securities.
Risk [Heading]	rr_RiskHeading	Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	It is important to understand that you can lose money by investing in the fund. Our allocation of assets among asset classes may hurt performance, and our efforts to diversify risk through the use of leverage and allocation decisions may not be successful. If the quantitative models or data that are used in managing the fund prove to be incorrect or incomplete, investment decisions made in reliance on the models or data may not produce the desired results and the fund may realize losses. The value of stocks and bonds in the fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general financial market conditions, changing market perceptions (including, in the case of bonds, perceptions about the risk of default and expectations about monetary policy or interest rates), changes in government intervention in the financial markets, and factors related to a specific issuer or industry. These and other factors may lead to increased volatility and reduced liquidity in the fund’s portfolio holdings. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. These risks are generally greater for small and midsize companies. Bond investments are subject to interest rate risk, which means the value of the fund’s bond investments is likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuer of the bond may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds, which may be considered speculative. Mortgage-backed investments, unlike traditional debt investments, are also subject to prepayment risk, which means that they may increase in value less than other bonds when interest rates decline and decline in value more than other bonds when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage-backed investments, in other investments with less attractive terms and yields. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments, particularly investments in emerging markets, may carry risks associated with potentially less stable economies or governments (such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation), and may be or become illiquid. Our active trading strategies may lose money or not earn a return sufficient to cover trading and other costs. REITs are subject to the risk of economic downturns that have an adverse impact on real estate markets. Commodity-linked notes are subject to the same risks as commodities, such as weather, disease, political, tax and other regulatory developments and other factors affecting the value of commodities. Our use of leverage obtained through derivatives increases the risk of investing in the fund by increasing investment exposure. Derivatives also involve the risk, in the case of many over-the-counter instruments, of the potential inability to terminate or sell derivatives positions and the potential failure of the other party to the instrument to meet its obligations. Our use of short selling may result in losses if the securities appreciate in value. The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text]	rr_RiskLoseMoney	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at putnam.com.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	putnam.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Please remember that past performance is not necessarily an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Annual total returns for class A shares before sales charges
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart does not reflect the impact of sales charges. If it did, performance would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Year-to-date performance through 6/30/19  11.86% Best calendar quarter Q1 2012   6.15% Worst calendar quarter Q4 2018 −12.06%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date performance
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Jun. 30, 2019
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	11.86%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best calendar quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Mar. 31, 2012
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	6.15%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst calendar quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2018
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(12.06%)
Performance Table Heading	rr_PerformanceTableHeading	Average annual total returns after sales charges (for periods ended 12/31/18)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for class A shares only and will vary for other classes.
Performance Table Footnotes	rr_PerformanceTableFootnotesTextBlock	The Putnam Dynamic Risk Allocation Blended Index is an unmanaged index administered by Putnam Management, 50% of which is the MSCI World Index (ND), 40% of which is the Bloomberg Barclays Global Aggregate Bond Index, and 10% of which is the S&P GSCI. After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement.
Putnam Dynamic Risk Allocation Fund | Putnam Dynamic Risk Allocation Blended Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(6.00%)
5 Years	rr_AverageAnnualReturnYear05	1.38%
Since Inception	rr_AverageAnnualReturnSinceInception	3.96%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class A
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[2]
Management fees	rr_ManagementFeesOverAssets	0.72%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.46%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.16%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 686
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	982
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,300
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 2,197
Annual Return 2012	rr_AnnualReturn2012	11.55%
Annual Return 2013	rr_AnnualReturn2013	4.00%
Annual Return 2014	rr_AnnualReturn2014	2.69%
Annual Return 2015	rr_AnnualReturn2015	(6.32%)
Annual Return 2016	rr_AnnualReturn2016	8.74%
Annual Return 2017	rr_AnnualReturn2017	13.46%
Annual Return 2018	rr_AnnualReturn2018	(11.00%)
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(16.12%)
5 Years	rr_AverageAnnualReturnYear05	(0.09%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.07%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class A | after taxes on distributions
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(16.53%)
5 Years	rr_AverageAnnualReturnYear05	(0.95%)
Since Inception	rr_AverageAnnualReturnSinceInception	1.22%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class A | after taxes on distributions and sale of fund shares
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(9.41%)
5 Years	rr_AverageAnnualReturnYear05	(0.29%)
Since Inception	rr_AverageAnnualReturnSinceInception	1.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class B
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	5.00%	[6]
Management fees	rr_ManagementFeesOverAssets	0.72%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	2.21%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.91%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 694
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	962
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,357
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,331
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	194
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	662
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,157
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 2,331
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(16.03%)
5 Years	rr_AverageAnnualReturnYear05	0.01%
Since Inception	rr_AverageAnnualReturnSinceInception	2.15%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class C
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[7]
Management fees	rr_ManagementFeesOverAssets	0.72%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	2.21%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.91%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 294
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	662
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,157
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,521
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	194
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	662
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,157
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 2,521
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(12.51%)
5 Years	rr_AverageAnnualReturnYear05	0.36%
Since Inception	rr_AverageAnnualReturnSinceInception	2.14%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class M
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	3.50%
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.72%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.75%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.96%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.66%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 513
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	916
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,344
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 2,532
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.57%)
5 Years	rr_AverageAnnualReturnYear05	(0.12%)
Since Inception	rr_AverageAnnualReturnSinceInception	1.89%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class R
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.72%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.71%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.41%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 144
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	510
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	900
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,994
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(11.17%)
5 Years	rr_AverageAnnualReturnYear05	0.86%
Since Inception	rr_AverageAnnualReturnSinceInception	2.66%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Putnam Dynamic Risk Allocation Fund | Class R6
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.72%
Other expenses	rr_OtherExpensesOverAssets	0.34%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.06%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.76%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 78
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	307
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	556
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,267
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(10.60%)	[8]
5 Years	rr_AverageAnnualReturnYear05	1.48%	[8]
Since Inception	rr_AverageAnnualReturnSinceInception	3.28%	[8]
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011	[8]
Putnam Dynamic Risk Allocation Fund | Class Y
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.72%
Other expenses	rr_OtherExpensesOverAssets	0.49%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.21%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.30%)	[4]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.91%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 93
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	354
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	636
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,439
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(10.79%)
5 Years	rr_AverageAnnualReturnYear05	1.36%
Since Inception	rr_AverageAnnualReturnSinceInception	3.18%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 19, 2011
Class A C Y | Putnam Mortgage Opportunities Fund
Prospectus [Line Items]	rr_ProspectusLineItems
Risk/Return [Heading]	rr_RiskReturnHeading	Fund summary
Objective [Heading]	rr_ObjectiveHeading	Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Putnam Mortgage Opportunities Fund seeks to maximize total return consistent with what Putnam Investment Management, LLC believes to be prudent risk. Total return is composed of capital appreciation and income.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses 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 $100,000 in Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 15 of the fund’s prospectus, in the Appendix to the fund’s prospectus, and in How to buy shares beginning on page II-1 of the fund’s statement of additional information (SAI).
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 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-related costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund’s shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund’s turnover rate in the most recent fiscal year was 1,012%.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	1012.00%
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 $100,000 in Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 15 of the fund?s prospectus, in the Appendix to the fund?s prospectus, and in How to buy shares beginning on page II-1 of the fund?s statement of additional information (SAI).
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 100,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then, except as indicated, redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund’s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Investments, risks, and performance
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Investments We invest mainly in mortgage-related fixed income securities and related derivatives that are either investment-grade or below-investment-grade in quality (sometimes referred to as “junk bonds”). Under normal circumstances, we invest at least 80% of the fund’s net assets in mortgages, mortgage-related fixed income securities and related derivatives (i.e., derivatives used to acquire exposure to, or whose underlying securities are, mortgages or mortgage-related securities). The fund generally uses the net unrealized gain or loss, or market value, of mortgage-related derivatives for purposes of this policy, but may use the notional value of a derivative if that is determined to be a more appropriate measure of the fund’s investment exposure. This policy may be changed only after 60 days’ notice to shareholders. We expect to invest in lower-rated, higher-yielding mortgage-backed securities, including non-agency residential mortgage-backed securities (which may be backed by non-qualified or “sub-prime” mortgages), commercial mortgage-backed securities, collateralized mortgage obligations (including interest only, principal only, and other prepayment derivatives), and agency mortgage-backed securities. Non-agency (i.e., privately issued) securities typically are lower-rated and higher yielding than securities issued or backed by agencies such as Ginnie Mae, Fannie Mae or Freddie Mac. While our emphasis will be on mortgage-backed securities, we may also invest to a lesser extent in other types of asset-backed securities. We may consider, among other factors, credit, interest rate, prepayment and liquidity risks, as well as general market conditions, when deciding whether to buy or sell investments. We typically use to a significant extent derivatives, including interest rate swaps, forward delivery contracts and total return swaps, options and swaptions on mortgage-backed securities and indices, for both hedging and non-hedging purposes, including to obtain or adjust exposure to mortgage-backed investments.
Risk [Heading]	rr_RiskHeading	Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	It is important to understand that you can lose money by investing in the fund. The value of investments in the fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, and factors related to a specific issuer, geography, industry or sector, such as the housing or real estate markets. These and other factors may lead to increased volatility and reduced liquidity in the fund’s portfolio holdings or in relevant markets. The risks associated with bond investments include interest rate risk, which means the value of the fund’s investments is likely to fall if interest rates rise. Bond investments are also subject to credit risk, which is the risk that the issuers of the fund’s investments may default on payment of interest or principal. Default risk is generally higher for non-qualified mortgages. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds, which may be considered speculative. Mortgage- and asset-backed investments, unlike traditional debt investments, are also subject to prepayment risk, which means that they may increase in value less than other bonds when interest rates decline and decline in value more than other bonds when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage- and asset-backed investments, in other investments with less attractive terms and yields. The fund’s investments in mortgage-backed securities and asset-backed securities, and in certain other securities and derivatives, may be or become illiquid. The fund’s concentration in an industry group composed of privately issued mortgage-backed securities and mortgage-backed securities issued or guaranteed by the U.S. government or its agencies or instrumentalities may make the fund’s net asset value more susceptible to economic, market, political and other developments affecting the residential and commercial real estate markets. Our use of derivatives may increase the risks of investing in the fund by increasing investment exposure (which may be considered leverage) or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions and the potential failure of the other party to the instrument to meet its obligations. The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text]	rr_RiskLoseMoney	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time. The performance shown is that of class I shares of the fund, which are not offered in this prospectus, and this performance has been adjusted to reflect the higher fees associated with class A, C and Y shares of the fund. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at putnam.com.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	putnam.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Please remember that past performance is not necessarily an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Annual total returns for class A shares before sales charges
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart does not reflect the impact of sales charges. If it did, performance would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Year-to-date performance through 6/30/19  4.38% Best calendar quarter Q3 2016   4.09% Worst calendar quarter Q1 2016 −4.10%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date performance
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Jun. 30, 2019
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	4.38%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best calendar quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2016
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	4.09%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst calendar quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2016
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(4.10%)
Performance Table Heading	rr_PerformanceTableHeading	Average annual total returns after sales charges (for periods ended 12/31/18)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for class A shares only and will vary for other classes.
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	The fund’s performance is compared to the ICE BofAML U.S. Treasury Bill Index, an unmanaged index that tracks the performance of U.S. dollar denominated U.S. Treasury bills, which represent obligations of the U.S. Government having a maturity of one year or less. The fund’s performance is also compared to the Bloomberg Barclays U.S. Mortgage Backed Securities (MBS) Index, an unmanaged index that tracks agency mortgage pass-through securities (both fixed-rate and hybrid adjustable-rate mortgages) guaranteed by Ginnie Mae (GNMA), Fannie Mae (FNMA), and Freddie Mac (FHLMC). Securities in the fund do not match those in the indexes and the performance of the fund will differ. After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement.
Class A C Y | Putnam Mortgage Opportunities Fund | ICE BofAML U.S. Treasury Bill Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	1.88%	[9]
Since Inception	rr_AverageAnnualReturnSinceInception	0.83%	[9]
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019	[9]
Class A C Y | Putnam Mortgage Opportunities Fund | Bloomberg Barclays U.S. MBS Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	0.99%
Since Inception	rr_AverageAnnualReturnSinceInception	1.46%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class A C Y | Putnam Mortgage Opportunities Fund | Class A
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	4.00%
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[2]
Management fees	rr_ManagementFeesOverAssets	0.55%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.28%	[10]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.08%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.21%)	[11]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.87%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 485
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	710
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	952
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,646
Annual Return 2016	rr_AnnualReturn2016	4.19%
Annual Return 2017	rr_AnnualReturn2017	5.66%
Annual Return 2018	rr_AnnualReturn2018	2.74%
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	(1.37%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.01%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class A C Y | Putnam Mortgage Opportunities Fund | Class A | after taxes on distributions
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(3.61%)
Since Inception	rr_AverageAnnualReturnSinceInception	0.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class A C Y | Putnam Mortgage Opportunities Fund | Class A | after taxes on distributions and sale of fund shares
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(0.80%)
Since Inception	rr_AverageAnnualReturnSinceInception	0.89%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class A C Y | Putnam Mortgage Opportunities Fund | Class C
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[7]
Management fees	rr_ManagementFeesOverAssets	0.55%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.28%	[10]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.83%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.21%)	[11]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.62%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 265
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	555
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	971
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,131
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	165
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	555
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	971
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 2,131
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	1.01%
Since Inception	rr_AverageAnnualReturnSinceInception	2.36%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class A C Y | Putnam Mortgage Opportunities Fund | Class Y
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.55%
Other expenses	rr_OtherExpensesOverAssets	0.28%	[10]
Total annual fund operating expenses	rr_ExpensesOverAssets	0.83%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.21%)	[11]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.62%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 63
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	244
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	440
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,006
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	3.04%
Since Inception	rr_AverageAnnualReturnSinceInception	3.41%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class I | Putnam Mortgage Opportunities Fund
Prospectus [Line Items]	rr_ProspectusLineItems
Risk/Return [Heading]	rr_RiskReturnHeading	Fund summary
Objective [Heading]	rr_ObjectiveHeading	Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Putnam Mortgage Opportunities Fund seeks to maximize total return consistent with what Putnam Investment Management, LLC believes to be prudent risk. Total return is composed of capital appreciation and income.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses you may pay if you buy and hold Class I shares of the fund.
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 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-related costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund’s shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund’s turnover rate in the most recent fiscal year was 1,012%.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	1012.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund’s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Investments, risks, and performance
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Investments We invest mainly in mortgage-related fixed income securities and related derivatives that are either investment-grade or below-investment-grade in quality (sometimes referred to as “junk bonds”). Under normal circumstances, we invest at least 80% of the fund’s net assets in mortgages, mortgage-related fixed income securities and related derivatives (i.e., derivatives used to acquire exposure to, or whose underlying securities are, mortgages or mortgage-related securities). The fund generally uses the net unrealized gain or loss, or market value, of mortgage-related derivatives for purposes of this policy, but may use the notional value of a derivative if that is determined to be a more appropriate measure of the fund’s investment exposure. This policy may be changed only after 60 days’ notice to shareholders. We expect to invest in lower-rated, higher-yielding mortgage-backed securities, including non-agency residential mortgage-backed securities (which may be backed by non-qualified or “sub-prime” mortgages), commercial mortgage-backed securities, collateralized mortgage obligations (including interest only, principal only, and other prepayment derivatives), and agency mortgage-backed securities. Non-agency (i.e., privately issued) securities typically are lower-rated and higher yielding than securities issued or backed by agencies such as Ginnie Mae, Fannie Mae or Freddie Mac. While our emphasis will be on mortgage-backed securities, we may also invest to a lesser extent in other types of asset-backed securities. We may consider, among other factors, credit, interest rate, prepayment and liquidity risks, as well as general market conditions, when deciding whether to buy or sell investments. We typically use to a significant extent derivatives, including interest rate swaps, forward delivery contracts and total return swaps, options and swaptions on mortgage-backed securities and indices, for both hedging and non-hedging purposes, including to obtain or adjust exposure to mortgage-backed investments.
Risk [Heading]	rr_RiskHeading	Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	It is important to understand that you can lose money by investing in the fund. The value of investments in the fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, and factors related to a specific issuer, geography, industry or sector, such as the housing or real estate markets. These and other factors may lead to increased volatility and reduced liquidity in the fund’s portfolio holdings or in relevant markets. The risks associated with bond investments include interest rate risk, which means the value of the fund’s investments is likely to fall if interest rates rise. Bond investments are also subject to credit risk, which is the risk that the issuers of the fund’s investments may default on payment of interest or principal. Default risk is generally higher for non-qualified mortgages. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds, which may be considered speculative. Mortgage- and asset-backed investments, unlike traditional debt investments, are also subject to prepayment risk, which means that they may increase in value less than other bonds when interest rates decline and decline in value more than other bonds when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage- and asset-backed investments, in other investments with less attractive terms and yields. The fund’s investments in mortgage-backed securities and asset-backed securities, and in certain other securities and derivatives, may be or become illiquid. The fund’s concentration in an industry group composed of privately issued mortgage-backed securities and mortgage-backed securities issued or guaranteed by the U.S. government or its agencies or instrumentalities may make the fund’s net asset value more susceptible to economic, market, political and other developments affecting the residential and commercial real estate markets. Our use of derivatives may increase the risks of investing in the fund by increasing investment exposure (which may be considered leverage) or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions and the potential failure of the other party to the instrument to meet its obligations. The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text]	rr_RiskLoseMoney	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at putnam.com.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	putnam.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Please remember that past performance is not necessarily an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Annual total returns for class I shares (for periods ended 5/31/19)
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart does not reflect the impact of sales charges. If it did, performance would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Year-to-date performance through 6/30/19  4.59% Best calendar quarter Q3 2016  4.14% Worst calendar quarter Q1 2016 −3.95%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date performance
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Jun. 30, 2019
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	4.59%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best calendar quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2016
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	4.14%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst calendar quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2016
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(3.95%)
Performance Table Heading	rr_PerformanceTableHeading	Average annual total returns (for periods ended 12/31/18)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for class A shares only and will vary for other classes.
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	The fund’s performance is compared to the ICE BofAML U.S. Treasury Bill Index, an unmanaged index that tracks the performance of U.S. dollar denominated U.S. Treasury bills, which represent obligations of the U.S. Government having a maturity of one year or less. The fund’s performance is also compared to the Bloomberg Barclays U.S. Mortgage Backed Securities (MBS) Index, an unmanaged index that tracks agency mortgage pass-through securities (both fixed-rate and hybrid adjustable-rate mortgages) guaranteed by Ginnie Mae (GNMA), Fannie Mae (FNMA), and Freddie Mac (FHLMC). Securities in the fund do not match those in the indexes and the performance of the fund will differ. After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement.
Class I | Putnam Mortgage Opportunities Fund | ICE BofAML U.S. Treasury Bill Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	1.88%	[9]
Since Inception	rr_AverageAnnualReturnSinceInception	0.83%	[9]
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019	[9]
Class I | Putnam Mortgage Opportunities Fund | Bloomberg Barclays U.S. MBS Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	0.99%
Since Inception	rr_AverageAnnualReturnSinceInception	1.46%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class I | Putnam Mortgage Opportunities Fund | Class I
Prospectus [Line Items]	rr_ProspectusLineItems
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 original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.55%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets
Other expenses	rr_OtherExpensesOverAssets	0.14%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.69%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.21%)	[11]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.48%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 49
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	200
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	363
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 839
Annual Return 2016	rr_AnnualReturn2016	4.64%
Annual Return 2017	rr_AnnualReturn2017	6.13%
Annual Return 2018	rr_AnnualReturn2018	3.14%
Label	rr_AverageAnnualReturnLabel	before taxes
1 Year	rr_AverageAnnualReturnYear01	3.14%
Since Inception	rr_AverageAnnualReturnSinceInception	3.55%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class I | Putnam Mortgage Opportunities Fund | Class I | after taxes on distributions
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	0.79%
Since Inception	rr_AverageAnnualReturnSinceInception	2.09%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019
Class I | Putnam Mortgage Opportunities Fund | Class I | after taxes on distributions and sale of fund shares
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	1.86%
Since Inception	rr_AverageAnnualReturnSinceInception	2.06%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 01, 2019

[1] Frank Russell Company is the source and owner of the trademarks, service marks and copyrights related to the Russell Indexes. Russell(R) is a trademark of Frank Russell Company.

[2] Applies only to certain redemptions of shares bought with no initial sales charge

[3] Although the fund's distribution and service (12b-1) plan provides for payments at annual rates (based on average net assets) of up to 0.35% on class A shares, no payments under the plan have been authorized by the Trustees. Should the Trustees decide in the future to approve payments under the plan, this prospectus will be revised.

[4] Reflects Putnam Investment Management, LLC's contractual obligation to limit certain fund expenses through September 30, 2020. This obligation may be modified or discontinued only with approval of the Board of Trustees.

[5] Performance for class P shares prior the their inception (8/31/16) is derived from the historical performance of class A shares and has not been adjusted for the lower investor servicing fees applicable to class P shares; had it, returns would have been higher.

[6] This charge is phased out over six years.

[7] This charge is eliminated after one year.

[8] Performance for class R6 shares prior to their inception (7/2/12) is derived from the historical performance of class Y shares and has not been adjusted for the lower investor servicing fees applicable to class R6 shares; had it, returns would have been higher.

[9] ICE Data Indices, LLC ("ICE BofAML"), used with permission. ICE BofAML permits use of the ICE BofAML indices and related data on an "as is" basis; makes no warranties regarding same; does not guarantee the suitability, quality, accuracy, timeliness, and/or completeness of the ICE BofAML indices or any data included in, related to, or derived therefrom; assumes no liability in connection with the use of the foregoing; and does not sponsor, endorse, or recommend Putnam Investments, or any of its products or services.

[10] Other expenses are based on expenses of class I shares (which are not offered in this prospectus) for the fund's last fiscal year, restated to reflect the higher investor servicing fees applicable to class A, C and Y shares.

[11] Reflects Putnam Investment Management, LLC's ("Putnam Management") contractual obligation to limit certain fund expenses through September 30, 2020. This obligation may be modified or discontinued only with approval of the Board of Trustees.