Business Combination - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Jan. 01, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Net sales	$ 4,173,775	$ 1,787,021
Income before income taxes	$ 216,112	9,016
Common stock, shares issued	206,858			116,829
Common stock, shares outstanding	206,858			116,829
BMC Stock Holdings, Inc.
Business Acquisition [Line Items]
Common stock price per share			$ 40.81
Common stock, shares issued			88,683
Common stock, shares outstanding			67,568
Preliminary fair value of intangible assets acquired			$ 1,470,000
Transaction related expenses assumed	$ 57,700
BMC Stock Holdings, Inc. | Level 3 | Customer Relationships
Business Acquisition [Line Items]
Preliminary fair value of intangible assets acquired		$ 1,500,000
BMC Stock Holdings, Inc. | Merger Agreement
Business Acquisition [Line Items]
Merger agreement date	Aug. 26, 2020
Net sales	$ 1,400,000
Income before income taxes	42,800
Transaction related costs, incurred	17,600
Common stock price per share				$ 40.81
Common stock, shares issued				88,700
Common stock, shares outstanding				900
Long-term debt, assumed	$ 359,800