Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Parenthetical) (Detail) - USD ($)		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenues		$ 122,008,000	$ 105,085,000
Sales revenues		(17,857,000)	(12,993,000)
Sales [Member]
Segment Reporting Information [Line Items]
Sales revenues		(16,825,000)	(12,091,000)
Enviroplex [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	2,805,000	2,018,000
Sales revenues	[1]	(2,805,000)	(2,018,000)
Mobile Modular [Member]
Segment Reporting Information [Line Items]
Revenues		65,092,000	53,851,000
Sales revenues		(8,360,000)	(4,890,000)
Operating Segments [Member] | Enviroplex [Member] | Sales [Member]
Segment Reporting Information [Line Items]
Revenues		2,805,000	2,813,000
Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Sales revenues		$ 0
Type of Revenue [Extensible List]		us-gaap:ProductMember
Inter-segment Eliminations [Member] | Mobile Modular [Member]
Segment Reporting Information [Line Items]
Sales revenues			$ 795,000
Type of Revenue [Extensible List]			us-gaap:ProductMember

[1] Gross Enviroplex sales revenues were $2,805 and $2,813 for the three months ended March 31, 2019 and 2018, respectively. There were $795 inter-segment sales to Mobile Modular in the three months ended March 31, 2018, which required elimination in consolidation. There were no inter-segment sales in the three months ended March 31, 2019.