| Form N-CSR Cover | 12 Months Ended |
| Aug. 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | PUTNAM ASSET ALLOCATION FUNDS |
| Entity Central Index Key | 0000914209 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Aug. 31, 2024 |
| Shareholder Report | 12 Months Ended | |
| Aug. 31, 2024 USD ($) $ / shares | ||
| Shareholder Report [Line Items] | ||
| Document Type | N-CSR | |
| Amendment Flag | false | |
| Registrant Name | PUTNAM ASSET ALLOCATION FUNDS | |
| Entity Central Index Key | 0000914209 | |
| Entity Investment Company Type | N-1A | |
| Document Period End Date | Aug. 31, 2024 | |
| Class A | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Putnam Multi-Asset Income Fund | |
| Class Name | Class A | |
| Trading Symbol | PMIAX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 $89 0.83% | [1] |
| Expenses Paid, Amount | $ 89 | |
| Expense Ratio, Percent | 0.83% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class A shares of Putnam Multi-Asset Income Fund returned 15.38%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class A 15.38 3.39 Class A (with sales charge) 10.77 2.49 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [2] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [2] |
| Holdings [Text Block] | [3] | |
| 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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 Multi-Asset Income Fund | |
| Class Name | Class C | |
| Trading Symbol | PMICX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 $169 1.58% | [4] |
| Expenses Paid, Amount | $ 169 | |
| Expense Ratio, Percent | 1.58% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class C shares of Putnam Multi-Asset Income Fund returned 14.50%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class C 14.50 2.59 Class C (with sales charge) 13.50 2.59 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [5] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 Multi-Asset Income Fund | |
| Class Name | Class P | |
| No Trading Symbol Flag | true | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 $44 0.41% | [7] |
| Expenses Paid, Amount | $ 44 | |
| Expense Ratio, Percent | 0.41% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class P shares of Putnam Multi-Asset Income Fund returned 15.85%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class P 15.85 4.57 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [8] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [8] |
| Holdings [Text Block] | [9] | |
| 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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 Multi-Asset Income Fund | |
| Class Name | Class R | |
| Trading Symbol | PMIRX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 $116 1.08% | [10] |
| Expenses Paid, Amount | $ 116 | |
| Expense Ratio, Percent | 1.08% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class R shares of Putnam Multi-Asset Income Fund returned 15.10%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class R 15.10 3.13 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [11] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 R5 | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Putnam Multi-Asset Income Fund | |
| Class Name | Class R5 | |
| Trading Symbol | PMILX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 R5 $59 0.55% | [13] |
| Expenses Paid, Amount | $ 59 | |
| Expense Ratio, Percent | 0.55% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class R5 shares of Putnam Multi-Asset Income Fund returned 15.68%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class R5 15.68 3.66 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [14] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [14] |
| Holdings [Text Block] | [15] | |
| 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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 R6 | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Putnam Multi-Asset Income Fund | |
| Class Name | Class R6 | |
| Trading Symbol | PMIVX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 R6 $49 0.45% | [16] |
| Expenses Paid, Amount | $ 49 | |
| Expense Ratio, Percent | 0.45% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class R6 shares of Putnam Multi-Asset Income Fund returned 15.81%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class R6 15.81 3.74 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [17] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [17] |
| Holdings [Text Block] | [18] | |
| 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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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 Y | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Putnam Multi-Asset Income Fund | |
| Class Name | Class Y | |
| Trading Symbol | PMIYX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Putnam Multi-Asset Income Fund for the period September 1, 2023, to August 31, 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 Y $63 0.58% | [19] |
| Expenses Paid, Amount | $ 63 | |
| Expense Ratio, Percent | 0.58% | |
| Factors Affecting Performance [Text Block] | HOW DID THE FUND PERFORM LAST YEAR AND WHAT AFFECTED ITS PERFORMANCE? For the twelve months ended August 31, 2024, Class Y shares of Putnam Multi-Asset Income Fund returned 15.66%. The Fund compares its performance to the Putnam Multi-Asset Income Blended Benchmark, which returned 12.92% for the same period. PERFORMANCE HIGHLIGHTS Top contributors to performance: Selection effects within these underlying funds: ↑ U.S. High Dividend Equity strategy ↑ Global Fixed Income strategy ↑ High Yield Fixed Income strategy There were no significant detractors to performance during the period. | |
| 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. | |
| Line Graph [Table Text Block] | ||
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS (%) Period Ended August 31, 2024 1 Year Since Inception (12/31/2019) Class Y 15.66 3.65 Bloomberg U.S. Aggregate Index 7.30 0.03 Putnam Multi-Asset Income Blended Benchmark 12.92 4.30 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund shares. | |
| 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/mutual-funds . Important data provider notices and terms available at www.franklintempletondatasources.com. | |
| Net Assets | $ 228,496,840 | |
| Holdings Count | $ / shares | 1,630 | [20] |
| Advisory Fees Paid, Amount | $ 404,446 | |
| Investment Company Portfolio Turnover | 143% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of August 31, 2024) Total Net Assets $228,496,840 Total Number of Portfolio Holdings * 1,630 Total Management Fee Paid $404,446 Portfolio Turnover Rate 143% | [20] |
| Holdings [Text Block] | [21] | |
| 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-advisors, Putnam Investments Limited (“PIL”) and The Putnam Advisory Company, LLC (“PAC”), indirect, wholly-owned subsidiaries 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 new sub-advisory contracts with PIL and PAC. 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 and sub-advisory agreement with PIL and PAC 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 sub-advisory agreement. This is a summary of certain changes to the Fund since September 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 December 30, 2024, 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] * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. * Includes derivatives, if applicable. U.S. Money Market Securities, if any, represent the market value weights of cash, short-term securities, and derivative notional offsets in the portfolio. Holdings and allocations may vary over time. | ||
| Shareholder Report, Line Graph (Details) - USD ($) | 12 Months Ended | ||||
| Aug. 31, 2024 | Aug. 31, 2023 | Aug. 31, 2022 | Aug. 31, 2021 | Aug. 31, 2020 | |
| Class A | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class A (with sales charge) | ||||
| Account Value | $ 11,218 | $ 9,722 | $ 9,419 | $ 10,783 | $ 9,980 |
| Class C | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class C (with sales charge) | ||||
| Account Value | $ 11,270 | 9,843 | 9,606 | 11,090 | 10,340 |
| Class P | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class P | ||||
| Account Value | $ 12,317 | 10,632 | 10,201 | 11,510 | 10,494 |
| Class R | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class R | ||||
| Account Value | $ 11,549 | 10,034 | 9,745 | 11,184 | 10,374 |
| Class R5 | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class R5 | ||||
| Account Value | $ 11,824 | 10,222 | 9,869 | 11,270 | 10,408 |
| Class R6 | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class R6 | ||||
| Account Value | $ 11,868 | 10,248 | 9,898 | 11,293 | 10,409 |
| Class Y | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Class Y | ||||
| Account Value | $ 11,821 | 10,220 | 9,879 | 11,281 | 10,409 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Bloomberg U.S. Aggregate Index [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||||
| Account Value | $ 10,015 | 9,334 | 9,447 | 10,676 | 10,685 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | 10,778 | 10,284 | 11,549 | 10,603 |
| Putnam Multi-Asset Income Blended Benchmark [Member] | |||||
| Account Value [Line Items] | |||||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | ||||
| Account Value | $ 12,171 | $ 10,778 | $ 10,284 | $ 11,549 | $ 10,603 |
| Shareholder Report, Average Annual Return (Details) | 12 Months Ended | 56 Months Ended |
| Aug. 31, 2024 | Aug. 31, 2024 | |
| Class A | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class A (with sales charge) | |
| Average Annual Return, Percent | 10.77% | 2.49% |
| Class C | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class C (with sales charge) | |
| Average Annual Return, Percent | 13.50% | 2.59% |
| Class P | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class P | |
| Average Annual Return, Percent | 15.85% | 4.57% |
| Class R | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class R | |
| Average Annual Return, Percent | 15.10% | 3.13% |
| Class R5 | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class R5 | |
| Average Annual Return, Percent | 15.68% | 3.66% |
| Class R6 | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class R6 | |
| Average Annual Return, Percent | 15.81% | 3.74% |
| Class Y | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class Y | |
| Average Annual Return, Percent | 15.66% | 3.65% |
| Without Sales Load [Member] | Class A | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class A | |
| Average Annual Return, Percent | 15.38% | 3.39% |
| Without Sales Load [Member] | Class C | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Class C | |
| Average Annual Return, Percent | 14.50% | 2.59% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Bloomberg U.S. Aggregate Index [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | |
| Average Annual Return, Percent | 7.30% | 0.03% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Putnam Multi-Asset Income Blended Benchmark [Member] | ||
| Average Annual Return [Line Items] | ||
| Line Graph and Table Measure Name | Putnam Multi-Asset Income Blended Benchmark | |
| Average Annual Return, Percent | 12.92% | 4.30% |
| Label | Element | Value |
| Class A | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class A | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class A | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class A | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class A | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class A | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class A | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class C | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class C | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class C | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class C | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class C | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class C | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class C | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class P | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class P | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class P | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class P | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class P | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class P | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class P | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class R | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class R | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class R | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class R | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class R | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class R | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class R | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class R5 | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class R5 | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class R5 | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class R5 | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class R5 | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class R5 | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class R5 | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class R6 | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class R6 | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class R6 | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class R6 | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class R6 | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class R6 | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class R6 | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
| Label | Element | Value |
| Class Y | U.S. Investment-Grade Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 52.50% |
| Class Y | U.S. Large-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 19.20% |
| Class Y | Global High-Yield Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.90% |
| Class Y | Emerging-Market Bonds [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 5.10% |
| Class Y | International Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.90% |
| Class Y | U.S. Small- and Mid-Cap Equity Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.20% |
| Class Y | U.S. Money Markets Securities [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.20% |
