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S000035596 [Member] Investment Objectives and Goals - Northern Trust Ultra-Short Fixed Income ETF
Oct. 31, 2025
Prospectus [Line Items]  
Risk/Return [Heading] Fund Summaries Northern Trust Ultra-Short Fixed Income ETF (formerly, FlexShares® Ultra-Short Income Fund)
Objective [Heading] Investment Objective
Objective, Primary [Text Block]
The Fund seeks maximum current income consistent with the preservation of capital and liquidity.