Expense Example	Oct. 31, 2024 USD ($)
BBH Select Series - Large Cap Fund \| Target Fund
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 73
Expense Example, with Redemption, 3 Years	228
Expense Example, with Redemption, 5 Years	396
Expense Example, with Redemption, 10 Years	882
BBH Select Series - Large Cap Fund \| Pro Forma Acquiring Fund
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	73
Expense Example, with Redemption, 3 Years	228
Expense Example, with Redemption, 5 Years	396
Expense Example, with Redemption, 10 Years	882
BBH Select Series - Mid Cap Fund \| Target Fund
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	83
Expense Example, with Redemption, 3 Years	259
Expense Example, with Redemption, 5 Years	450
Expense Example, with Redemption, 10 Years	1,003
BBH Select Series - Mid Cap Fund \| Pro Forma Acquiring Fund
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	83
Expense Example, with Redemption, 3 Years	259
Expense Example, with Redemption, 5 Years	450
Expense Example, with Redemption, 10 Years	$ 1,003

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