Shareholder Report, Line Graph (Details) 74200172000_Putnam Strategic Intermediate Municipal Fund_Class R6_TSR Annual {Class R6} - USD ($) |
12 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Jul. 31, 2025 |
Jul. 31, 2024 |
Jul. 31, 2023 |
Jul. 31, 2022 |
Jul. 31, 2021 |
Jul. 31, 2020 |
Jul. 31, 2019 |
Jul. 31, 2018 |
Jul. 31, 2017 |
Jul. 31, 2016 |
Jul. 31, 2026 |
|
| Class R6 | |||||||||||
| Account Value [Line Items] | |||||||||||
| Line Graph and Table Measure Name | Class R6 | ||||||||||
| Accumulated Value | $ 12,152 | $ 12,027 | $ 11,403 | $ 11,232 | $ 11,918 | $ 11,368 | $ 10,882 | $ 10,137 | $ 9,974 | $ 10,000 | $ 12,841 |
| Bloomberg Municipal Bond Index [Member] | |||||||||||
| Account Value [Line Items] | |||||||||||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | ||||||||||
| Accumulated Value | 11,522 | 11,523 | 11,107 | 11,005 | 11,824 | 11,447 | 10,865 | 10,125 | 10,026 | 10,000 | $ 12,129 |
| Putnam Strategic Intermediate Municipal Linked Benchmark [Member] | |||||||||||
| Account Value [Line Items] | |||||||||||
| Line Graph and Table Measure Name | Putnam Strategic Intermediate Municipal Linked Benchmark | ||||||||||
| Accumulated Value | 11,752 | 11,537 | 11,186 | 11,080 | 11,734 | 11,447 | 10,865 | 10,125 | 10,026 | 10,000 | $ 12,192 |
| Bloomberg 3-15 Year Blend Municipal Bond Index [Member] | |||||||||||
| Account Value [Line Items] | |||||||||||
| Line Graph and Table Measure Name | Bloomberg 3-15 Year Blend Municipal Bond Index | ||||||||||
| Accumulated Value | $ 11,671 | $ 11,458 | $ 11,109 | $ 11,003 | $ 11,653 | $ 11,358 | $ 10,809 | $ 10,099 | $ 10,043 | $ 10,000 | $ 12,108 |