Prospectus 1 [Member] Investment Risks - Prospectus 1 - Putnam Mortgage Opportunities Fund	May 31, 2025
Bond investments risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Bond investments risk: The risks associated with bond investments include interest rate risk, which is the risk that 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 issuers of the fund’s investments may default on payment of interest or principal. Bond investments may be more susceptible to downgrades or defaults during economic downturns or other periods of economic stress. 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 (a significant part of the fund’s investments), which can be more sensitive to changes in markets, credit conditions, and interest rates, and 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. The fund 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- 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 residential and commercial 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 and the servicing of mortgage loans secured by real estate properties. During periods of difficult economic conditions, delinquencies and losses on commercial mortgage-backed investments in particular generally increase, including as a result of the effects of those conditions on commercial real estate markets, the ability of commercial tenants to make loan payments, and the ability of a property to attract and retain commercial tenants.
Derivatives risks [Member]
Prospectus [Line Items]
Risk [Text Block]	Derivatives risk: The fund’s 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 derivative positions and the potential failure of the other party to the instrument to meet its obligations. The risk of a party failing to meet its obligations may increase if the fund has significant exposure to that counterparty. The value of derivatives may move in unexpected ways due to unanticipated market movements, the use of leverage, imperfect correlation between the derivative instrument and the reference asset, or other factors, especially in unusual market conditions, and volatility in the value of derivatives could adversely impact the fund’s returns, obligations and exposures. Derivatives are also subject to other risks, including liquidity risk (e.g., liquidity demands arising from the requirement to make payments to a derivative counterparty), operational risk (e.g., settlement issues or system failures) and legal risk (e.g., insufficient legal documentation or contract enforceability issues).
Large shareholder transaction risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Large shareholder transaction risk: The fund is subject to the risk that shareholders will purchase or redeem large quantities of shares of the fund. The fund may be an investment option for mutual funds that are managed by the Investment Manager and its affiliates as “funds of funds.” Additionally, other investors from time to time may make substantial investments in the fund. Such shareholders may at times be considered to control the fund. In addition, a large number of shareholders may collectively purchase or redeem fund shares in large amounts rapidly or unexpectedly. Large shareholder transactions may adversely affect the fund’s liquidity and net assets. These redemptions may also adversely affect the fund’s performance if the fund is forced to sell securities, which may also increase the fund’s brokerage costs.
Frequent trading risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Frequent trading risk: The fund expects to engage in frequent trading. Funds with high turnover may be more likely to realize capital gains that must be distributed to shareholders as taxable income and may incur higher transaction costs than funds with relatively lower turnover, which may detract from performance.
Management and operational risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Management and operational risk: There is no guarantee that the investment techniques, analyses, or judgments that the Investment Manager applies in making investment decisions for the fund will produce the intended outcome or that the investments selected for the fund will perform as well as other securities that were not selected for the fund. The Investment Manager, or the fund’s other service providers, may experience disruptions or operating errors that could negatively impact the fund.
Market risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Market risk: 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, outbreaks of infectious illnesses or other widespread public health issues, and factors related to a specific issuer, asset class, 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, may negatively impact the fund’s performance, and may exacerbate other risks to which the fund is subject.
Risk Lose Money [Member]
Prospectus [Line Items]
Risk [Text Block]	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured [Member]
Prospectus [Line Items]
Risk [Text Block]	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Prospectus 1 [Member] Investment Risks - Prospectus 1 - Putnam Mortgage Opportunities Fund

May 31, 2025

Bond investments risk: The risks associated with bond investments include interest rate risk, which is the risk that 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 issuers of the fund’s investments may default on payment of interest or principal. Bond investments may be more susceptible to downgrades or defaults during economic downturns or other periods of economic stress. 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 (a significant part of the fund’s investments), which can be more sensitive to changes in markets, credit conditions, and interest rates, and 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. The fund 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- 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 residential and commercial 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 and the servicing of mortgage loans secured by real estate properties. During periods of difficult economic conditions, delinquencies and losses on commercial mortgage-backed investments in particular generally increase, including as a result of the effects of those conditions on commercial real estate markets, the ability of commercial tenants to make loan payments, and the ability of a property to attract and retain commercial tenants.

Derivatives risks [Member]

Prospectus [Line Items]

Risk [Text Block]

Derivatives risk: The fund’s 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 derivative positions and the potential failure of the other party to the instrument to meet its obligations. The risk of a party failing to meet its obligations may increase if the fund has significant exposure to that counterparty. The value of derivatives may move in unexpected ways due to unanticipated market movements, the use of leverage, imperfect correlation between the derivative instrument and the reference asset, or other factors, especially in unusual market conditions, and volatility in the value of derivatives could adversely impact the fund’s returns, obligations and exposures. Derivatives are also subject to other risks, including liquidity risk (e.g., liquidity demands arising from the requirement to make payments to a derivative counterparty), operational risk (e.g., settlement issues or system failures) and legal risk (e.g., insufficient legal documentation or contract enforceability issues).

Large shareholder transaction risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Large shareholder transaction risk: The fund is subject to the risk that shareholders will purchase or redeem large quantities of shares of the fund. The fund may be an investment option for mutual funds that are managed by the Investment Manager and its affiliates as “funds of funds.” Additionally, other investors from time to time may make substantial investments in the fund. Such shareholders may at times be considered to control the fund. In addition, a large number of shareholders may collectively purchase or redeem fund shares in large amounts rapidly or unexpectedly. Large shareholder transactions may adversely affect the fund’s liquidity and net assets. These redemptions may also adversely affect the fund’s performance if the fund is forced to sell securities, which may also increase the fund’s brokerage costs.

Frequent trading risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Frequent trading risk: The fund expects to engage in frequent trading. Funds with high turnover may be more likely to realize capital gains that must be distributed to shareholders as taxable income and may incur higher transaction

costs than funds with relatively lower turnover, which may detract from performance.

Management and operational risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Management and operational risk: There is no guarantee that the investment techniques, analyses, or judgments that the Investment Manager applies in making investment decisions for the fund will produce the intended outcome or that the investments selected for the fund will perform as well as other securities that were not selected for the fund. The Investment Manager, or the fund’s other service providers, may experience disruptions or operating errors that could negatively impact the fund.

Market risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Market risk: 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, outbreaks of infectious illnesses or other widespread public health issues, and factors related to a specific issuer, asset class, 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, may negatively impact the fund’s performance, and may exacerbate other risks to which the fund is subject.

Risk Lose Money [Member]

Prospectus [Line Items]

Risk [Text Block]

It is important to understand that you can lose money by investing in the fund.

Risk Not Insured [Member]

Prospectus [Line Items]

Risk [Text Block]

An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.