Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Parenthetical) (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenues		$ 616,833,000	$ 572,554,000	$ 570,230,000
Sales revenues		$ (128,759,000)	$ (128,371,000)	(115,303,000)
Type of Revenue [Extensible List]		Sales [Member]	Sales [Member]
Sales [Member]
Segment Reporting Information [Line Items]
Sales revenues		$ (125,235,000)	$ (124,604,000)	(110,229,000)
Enviroplex [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	31,081,000	32,737,000	39,814,000
Sales revenues	[1]	(31,081,000)	(32,737,000)	(39,814,000)
Mobile Modular [Member]
Segment Reporting Information [Line Items]
Revenues		363,316,000	321,524,000	301,010,000
Sales revenues		(70,417,000)	(65,278,000)	(49,299,000)
Operating Segments [Member] | Enviroplex [Member] | Sales [Member]
Segment Reporting Information [Line Items]
Revenues		32,095,000	34,014,000	39,814,000
Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Sales revenues				$ 0
Type of Revenue [Extensible List]				Sales [Member]
Inter-segment Eliminations [Member] | Mobile Modular [Member]
Segment Reporting Information [Line Items]
Sales revenues		$ 1,014,000	$ 1,277,000

[1] Gross Enviroplex sales revenues were $32,095, $34,014 and $39,814 in 2021, 2020 and 2019, respectively.  There were $1,014 and $1,277 inter-segment sales to Mobile Modular in 2021 and 2020, which have been eliminated in consolidation.  There were no inter-segment sales in 2019.