S000003997 [Member] Expense Example, No Redemption - Putnam Sustainable Retirement 2045 Fund - Class C Shares |
Jul. 31, 2025
USD ($)
|
|---|---|
| Prospectus [Line Items] | |
| Expense Example, No Redemption, 1 Year | $ 173 |
| Expense Example, No Redemption, 3 Years | 536 |
| Expense Example, No Redemption, 5 Years | 1,071 |
| Expense Example, No Redemption, 10 Years | $ 2,346 |