Shareholder Report, Average Annual Return (Details) 1014021_Franklin Municipal Green Bond ETF_Single Class_TSR Annual {Single Class} |
12 Months Ended | 60 Months Ended | 103 Months Ended |
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2026 |
Mar. 31, 2026 |
|
| Franklin Municipal Green Bond ETF | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Franklin Municipal Green Bond ETF (NAV) | ||
| Average Annual Return, Percent | 4.62% | 0.58% | 2.17% |
| Bloomberg Municipal Bond Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | ||
| Average Annual Return, Percent | 4.29% | 0.84% | 2.08% |