S000054498 [Member] Expense Example - Northern Trust STOXX US ESG Select ETF - FlexShares STOXX US ESG Select Index Fund	Oct. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 33
Expense Example, with Redemption, 3 Years	105
Expense Example, with Redemption, 5 Years	184
Expense Example, with Redemption, 10 Years	$ 417

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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