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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Proposed Merger with BMC Stock Holdings, Inc. and other Business Combinations - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
	Jan. 09, 2020	Sep. 30, 2020
Bianchi & Company, Inc.
Business Acquisition [Line Items]
Cash consideration for certain assets acquired	$ 15,900
Fair value of intangible assets acquired	9,440
Bianchi & Company, Inc. \| Level 3 \| Customer Relationships
Business Acquisition [Line Items]
Fair value of intangible assets acquired	$ 9,400
Merger Agreement
Business Acquisition [Line Items]
Conversion of common stock issuable		1.3125
Builders FirstSource, Inc. \| Merger Agreement
Business Acquisition [Line Items]
Common stock shares held		57.00%
BMC Stock Holdings, Inc. \| Merger Agreement
Business Acquisition [Line Items]
Common stock shares held		43.00%