Shareholder Report, Line Graph (Details) 1014020_Franklin Dynamic Municipal Bond ETF_Single Class_TSR Annual {Single Class} - USD ($) |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
Mar. 31, 2022 |
Mar. 31, 2021 |
Mar. 31, 2020 |
Mar. 31, 2019 |
Mar. 31, 2018 |
Aug. 30, 2017 |
Mar. 31, 2026 |
|
| Franklin Dynamic Municipal Bond ETF | ||||||||||
| Account Value [Line Items] | ||||||||||
| Line Graph and Table Measure Name | Franklin Dynamic Municipal Bond ETF (NAV) | |||||||||
| Accumulated Value | $ 12,076 | $ 11,616 | $ 10,920 | $ 11,010 | $ 11,433 | $ 10,505 | $ 10,339 | $ 9,847 | $ 10,000 | $ 12,757 |
| Bloomberg Municipal Bond Index [Member] | ||||||||||
| Account Value [Line Items] | ||||||||||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | |||||||||
| Accumulated Value | 11,443 | 11,305 | 10,963 | 10,934 | 11,446 | 10,848 | 10,446 | 9,913 | 10,000 | $ 11,934 |
| Bloomberg Municipal 1-15 Year Index [Member] | ||||||||||
| Account Value [Line Items] | ||||||||||
| Line Graph and Table Measure Name | Bloomberg Municipal 1-15 Year Index | |||||||||
| Accumulated Value | $ 11,415 | $ 11,238 | $ 10,951 | $ 10,778 | $ 11,251 | $ 10,724 | $ 10,381 | $ 9,878 | $ 10,000 | $ 11,927 |