S000062125 [Member] Expense Example - FlexShares High Yield Value-Scored Bond Index Fund - FlexShares High Yield Value-Scored Bond Index Fund	Oct. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 38
Expense Example, with Redemption, 3 Years	121
Expense Example, with Redemption, 5 Years	212
Expense Example, with Redemption, 10 Years	$ 479

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