S000038875 [Member] Expense Example - Northern Trust Quality Dividend Defensive ETF - FlexShares Quality Dividend Defensive Index Fund	Oct. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 40
Expense Example, with Redemption, 3 Years	127
Expense Example, with Redemption, 5 Years	223
Expense Example, with Redemption, 10 Years	$ 504

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