Net Income per Common Share - Additional Information (Detail) - shares shares in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Stock Options
Earnings Per Share [Line Items]
Securities included in the computation of diluted EPS	1.5	3.0	1.5	3.0
Restricted Stock Units (RSUs)
Earnings Per Share [Line Items]
Securities included in the computation of diluted EPS	2.1	2.2	2.1	2.2

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were included in the computation of diluted EPS or EPU because to do so would decrease EPS or EPU amounts or increase loss per share or unit amounts for the period presented.

No definition available.

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Namespace Prefix:	bldr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration