Label	Element	Value
Western Asset Bond ETF \| Corporate Bonds & Notes [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	32.90%
Western Asset Bond ETF \| Mortgage-Backed Securities [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	25.50%
Western Asset Bond ETF \| U.S. Government & Agency Obligations [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	17.60%
Western Asset Bond ETF \| Collateralized Mortgage Obligations [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	10.10%
Western Asset Bond ETF \| Asset-Backed Securities [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	9.80%
Western Asset Bond ETF \| Sovereign Bonds [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	1.40%
Western Asset Bond ETF \| Senior Loans [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	1.30%
Western Asset Bond ETF \| Purchased Options [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	0.00%
Western Asset Bond ETF \| Common Stocks [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	0.00%
Western Asset Bond ETF \| Short-Term Investments [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	1.40%