Label	Element	Value
Franklin U.S. Mid Cap Multifactor Index ETF \| Industrials [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	20.30%
Franklin U.S. Mid Cap Multifactor Index ETF \| Consumer Discretionary [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	18.10%
Franklin U.S. Mid Cap Multifactor Index ETF \| Financials [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	15.40%
Franklin U.S. Mid Cap Multifactor Index ETF \| Health Care [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	12.50%
Franklin U.S. Mid Cap Multifactor Index ETF \| Consumer Staples [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	9.30%
Franklin U.S. Mid Cap Multifactor Index ETF \| Information Technology [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	8.20%
Franklin U.S. Mid Cap Multifactor Index ETF \| Energy [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	5.90%
Franklin U.S. Mid Cap Multifactor Index ETF \| Real Estate [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	3.90%
Franklin U.S. Mid Cap Multifactor Index ETF \| Communication Services [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	3.30%
Franklin U.S. Mid Cap Multifactor Index ETF \| Utilities [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	2.10%
Franklin U.S. Mid Cap Multifactor Index ETF \| Materials [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	0.90%
Franklin U.S. Mid Cap Multifactor Index ETF \| Short-Term Investments [Member]
Holdings [Line Items]	oef_HoldingsLineItems
Percent of Total Investments	oef_PctOfTotalInv	0.10%