Revenue - Additional Information (Detail)	3 Months Ended
Revenue - Additional Information (Detail)	Mar. 31, 2026	Mar. 31, 2025
Disaggregation Of Revenue [Line Items]
Percentage of recognized revenue from contract liability balances	72.00%	70.00%
Percentage change in previously reported product category sales	1.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Builders FirstSource, Inc. 10-Q