S000051718 [Member] Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Putnam Sustainable Retirement 2060 Fund | Class A Shares | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 13.44% | 15.86% | 23.11% | (16.24%) | 17.91% | 14.38% | 20.83% | (9.80%) | 20.58% | 6.84% |