Putnam Research Fund (PNRAX) N-CSR22 Nov 24Certified annual shareholder report (management investment company)Financial data

Company Profile

Form N-CSR Cover

Form N-CSR Cover	12 Months Ended
Form N-CSR Cover	Sep. 30, 2024
Shareholder Report [Line Items]
Document Type	N-CSR
Amendment Flag	false
Registrant Name	Putnam Investment Funds
Entity Central Index Key	0000932101
Entity Investment Company Type	N-1A
Document Period End Date	Sep. 30, 2024

Shareholder Report

Shareholder Report	12 Months Ended
Shareholder Report	Sep. 30, 2024 USD ($) $ / shares
Shareholder Report [Line Items]
Document Type	N-CSR
Amendment Flag	false
Registrant Name	Putnam Investment Funds
Entity Central Index Key	0000932101
Entity Investment Company Type	N-1A
Document Period End Date	Sep. 30, 2024
Class A
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class A
Trading Symbol	PGDXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $50 0.49%
Expenses Paid, Amount	$ 50
Expense Ratio, Percent	0.49%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class A shares of the Putnam Government Money Market Fund was 4.45% and the seven-day effective yield was 4.45%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[1]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[1]
Holdings [Text Block]		[2]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents
Class C
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class C
Trading Symbol	PGEXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $50 0.49%
Expenses Paid, Amount	$ 50
Expense Ratio, Percent	0.49%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class C shares of the Putnam Government Money Market Fund was 4.45% and the seven-day effective yield was 4.45%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[3]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[3]
Holdings [Text Block]		[4]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents
Class G
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class G
Trading Symbol	PGGXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class G $37 0.36%
Expenses Paid, Amount	$ 37
Expense Ratio, Percent	0.36%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class G shares of the Putnam Government Money Market Fund was 4.58% and the seven-day effective yield was 4.58%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[5]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[5]
Holdings [Text Block]		[6]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents
Class I
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class I
Trading Symbol	PGKXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I $37 0.36%
Expenses Paid, Amount	$ 37
Expense Ratio, Percent	0.36%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class I shares of the Putnam Government Money Market Fund was 4.58% and the seven-day effective yield was 4.58%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[7]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[7]
Holdings [Text Block]		[8]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents
Class P
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class P
Trading Symbol	PGLXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class P $37 0.36%
Expenses Paid, Amount	$ 37
Expense Ratio, Percent	0.36%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class P shares of the Putnam Government Money Market Fund was 4.58% and the seven-day effective yield was 4.58%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[9]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[9]
Holdings [Text Block]		[10]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents
Class R
Shareholder Report [Line Items]
Fund Name	Putnam Government Money Market Fund
Class Name	Class R
Trading Symbol	PGRXX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains important information about Putnam Government Money Market Fund for the period October 1, 2023, to September 30, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) 225-1581 .
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	(800) 225-1581
Additional Information Website	https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]	WHAT WERE THE FUND COSTS FOR THE LAST YEAR? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R $50 0.49%
Expenses Paid, Amount	$ 50
Expense Ratio, Percent	0.49%
Factors Affecting Performance [Text Block]	HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? As of September 30, 2024, the seven-day current yield for Class R shares of the Putnam Government Money Market Fund was 4.45% and the seven-day effective yield was 4.45%. The seven-day current yield represents net interest income generated by the Fund’s investments for the past seven days and assumes income is generated each week over a 365-day period. The seven-day effective yield assumes reinvestment of the coupon (interest payments) and will typically be slightly higher than the current yield because of the compounding effect on investment returns. The Fund has maintained a shorter weighted average maturity (WAM) posture due to our view that the U.S. Federal Reserve (Fed) rate cutting cycle will be slower and shallower relative to market expectations. As a result, the Fund’s principal exposure is to overnight repurchase agreements that are collateralized by U.S. Treasuries and/or government agency mortgage-backed securities. Additionally, the Fund maintained term exposure in the 1 to 10-month maturity range with investments in U.S. Treasuries where we saw opportunities to lock in higher yields. The Fund decreased its exposure to Federal Home Loan Bank and Federal Farm Credit Bank securities as spreads are now less attractive, in our view.
Performance Past Does Not Indicate Future [Text]	The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.
Material Change Date	Oct. 01, 2023
Updated Performance Information Location [Text Block]	For current month-end performance, please call Franklin Templeton at (800) 225-1581 or visit https://www.franklintempleton.com/investments/options/money-market-funds .
Net Assets	$ 369,355,157
Holdings Count \| $ / shares	13	[11]
Advisory Fees Paid, Amount	$ 894,495
Additional Fund Statistics [Text Block]	KEY FUND STATISTICS (as of September 30, 2024) Total Net Assets $369,355,157 Total Number of Portfolio Holdings * 13 Total Management Fee Paid $894,495	[11]
Holdings [Text Block]		[12]
Material Fund Change [Text Block]	HOW HAS THE FUND CHANGED? On May 31, 2023, Franklin Resources, Inc. (“Franklin Resources”) and Great-West Lifeco Inc., the parent company of Putnam U.S. Holdings I, LLC (“Putnam Holdings”), announced that they had entered into a definitive agreement for a subsidiary of Franklin Resources to acquire Putnam Holdings in a stock and cash transaction (the “Transaction”). The Transaction was completed on January 1, 2024. As part of the Transaction, your Fund’s then-current investment advisor, Putnam Investment Management, LLC (“Putnam Management”), a wholly-owned subsidiary of Putnam Holdings, and your Fund’s sub-advisor, Putnam Investments Limited (“PIL”), an indirect, wholly-owned subsidiary of Putnam Holdings, became indirect, wholly-owned subsidiaries of Franklin Resources. In connection with the Transaction, shareholders of your Fund approved a new management contract with Putnam Management and a new sub-advisory contract with PIL. The new contracts are identical to the previous contracts, except for the effective dates, initial terms, updates to fund names as necessary to reflect previous name changes, and certain non-substantive changes. Effective July 15, 2024, Putnam Management transferred its management contract for your Fund to Franklin Advisers, Inc. (“Franklin Advisers”), and Franklin Advisers replaced Putnam Management as the investment advisor to your Fund. In connection with the transfer, your Fund’s portfolio managers, along with supporting research analysts and certain other investment staff of Putnam Management, also became employees of Franklin Advisers. Putnam Management also transferred to Franklin Advisers its sub-management agreement with PIL in respect of your Fund. Franklin Advisers is an indirect, wholly-owned subsidiary of Franklin Resources. In addition, effective July 15, 2024, Franklin Advisers retained Putnam Management as a sub-advisor to your Fund pursuant to a new subadvisory agreement. This is a summary of certain changes to the Fund since October 1, 2023 . For more complete information, you may review the Fund’s current prospectus and any applicable supplements and the Fund’s next prospectus, which we expect to be available by February 1, 2025, at https://www.franklintempleton.com/regulatory-fund-documents or upon request at (800) 225-1581 or funddocuments putnam.com .
Updated Prospectus Phone Number	(800) 225-1581
Updated Prospectus Email Address	funddocuments@putnam.com
Updated Prospectus Web Address	https://www.franklintempleton.com/regulatory-fund-documents

[1] * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash and other unclassified assets in the portfolio and may show a negative market value percentage as a result of the timing of trade-date and settlement-date transactions. Holdings and allocations may vary over time.

Shareholder Report, Holdings (D

Label	Element	Value
Class A \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class A \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class A \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)

Shareholder Report, Holdings _2

Label	Element	Value
Class G \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class G \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class G \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)

Shareholder Report, Holdings _3

Label	Element	Value
Class C \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class C \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class C \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)

Shareholder Report, Holdings _4

Label	Element	Value
Class I \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class I \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class I \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)

Shareholder Report, Holdings _5

Label	Element	Value
Class P \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class P \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class P \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)

Shareholder Report, Holdings _6

Label	Element	Value
Class R \| Repurchase Agreements [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	93.80%
Class R \| U.S. Treasury Debt [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	6.60%
Class R \| Cash and Equivalents [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Net Asset Value	oef_PctOfNav	(0.40%)