S000039730 [Member] Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
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 |
Dec. 31, 2015 |
|
| Putnam Short Term Investment Fund | Class P | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 5.45% | 5.34% | 1.73% | 0.10% | 0.65% | 2.36% | 2.02% | 1.03% | 0.46% | 0.12% |