Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021		Sep. 30, 2020
Segment Reporting Information [Line Items]
Revenues		$ 173,292	$ 156,448	$ 440,922		$ 423,574
Sales revenues				$ (83,115)		$ (90,275)
Type of Revenue [Extensible List]				Sales [Member]		Sales [Member]
Sales [Member]
Segment Reporting Information [Line Items]
Sales revenues		(37,636)	(42,331)	$ (80,503)		$ (87,366)
Enviroplex [Member]
Segment Reporting Information [Line Items]
Revenues		5,541	5,914	14,897	[1]	16,616	[1]
Sales revenues	[1]			(14,897)		(16,616)
Mobile Modular [Member]
Segment Reporting Information [Line Items]
Revenues		$ 110,394	$ 95,413	263,614		245,373
Sales revenues				(49,770)		(52,910)
Operating Segments [Member] | Enviroplex [Member] | Sales [Member]
Segment Reporting Information [Line Items]
Revenues				15,909		17,892
Inter-segment Eliminations [Member] | Mobile Modular [Member]
Segment Reporting Information [Line Items]
Sales revenues				$ 1,012		$ 1,276

[1] Gross Enviroplex sales revenues were $15,909 and $17,892 for the nine months ended September 30, 2021 and 2020, respectively. There were $1,012 and $1,276 inter-segment sales to Mobile Modular in the nine months ended September 30, 2021 and 2020, respectively, which required elimination in consolidation.