Shareholder Report, Average Annual Return (Details) 998000_Franklin Short Duration U.S. Government ETF_Single Class_TSR Annual {Single Class} |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2026 |
Mar. 31, 2026 |
|
| Franklin Short Duration U.S. Government ETF | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Franklin Short Duration U.S. Government ETF (NAV) | ||
| Average Annual Return, Percent | 4.49% | 2.38% | 2.03% |
| Bloomberg U.S. Aggregate Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||
| Average Annual Return, Percent | 4.35% | 0.31% | 1.70% |
| Bloomberg U.S. Government (1-3 Year) Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg U.S. Government (1-3 Year) Index | ||
| Average Annual Return, Percent | 3.77% | 1.83% | 1.78% |