S000048336 [Member] Expense Example - Bridge Builder Small/Mid Cap Growth Fund - Bridge Builder Small/Mid Cap Growth Fund	Jun. 30, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 35
Expense Example, with Redemption, 3 Years	179
Expense Example, with Redemption, 5 Years	336
Expense Example, with Redemption, 10 Years	$ 792

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