Acquisitions - Summary of Preliminary Purchase Price Allocations Reflecting Estimated Fair Values of Assets Acquired and Liabilities Assumed (Parenthetical) (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	May 17, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Allowance for doubtful accounts	$ 2,225		$ 2,100
Design Space Modular Buildings PNW, LP [Member]
Business Acquisition [Line Items]
Allowance for doubtful accounts		$ 125