Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Rental revenues		$ 120,332	$ 110,247
Rental related services revenues		29,580	27,132
Sales and other revenues		37,915	26,339
Total revenues		187,827	163,718
Depreciation of rental equipment		22,366	21,833
Gross profit		93,268	77,367
Selling and administrative expenses		59,818	57,498
Other income		(9,281)
Income (loss) from operations		42,731	19,869
Interest (expense) income allocation		(12,704)	(7,464)
Income (loss) before provision for income taxes		29,895	12,631
Rental equipment acquisitions		67,784	72,211
Accounts receivable, net (period end)		211,950	177,006
Rental equipment, at cost (period end)		1,957,077	1,813,885
Rental equipment, net book value (period end)		1,368,542	1,267,268
Mobile Modular [Member]
Segment Reporting Information [Line Items]
Rental revenues		76,496	64,056
Rental related services revenues		24,133	21,534
Sales and other revenues		26,956	18,337
Total revenues		127,585	103,927
Depreciation of rental equipment		9,874	8,657
Gross profit		61,845	46,171
Selling and administrative expenses		40,087	38,456
Other income		(6,220)
Income (loss) from operations		27,978	7,715
Interest (expense) income allocation		(9,799)	(5,387)
Income (loss) before provision for income taxes		18,179	2,328
Rental equipment acquisitions		59,263	54,448
Accounts receivable, net (period end)		166,382	135,104
Rental equipment, at cost (period end)		1,345,919	1,200,869
Rental equipment, net book value (period end)		$ 1,013,965	$ 901,090
Utilization (period end)	[1]	78.50%	79.50%
Average utilization	[1]	78.70%	79.40%
Portable Storage [Member]
Segment Reporting Information [Line Items]
Rental revenues		$ 18,407	$ 17,057
Rental related services revenues		4,723	4,718
Sales and other revenues		1,630	955
Total revenues		24,760	22,730
Depreciation of rental equipment		965	787
Gross profit		17,103	15,451
Selling and administrative expenses		9,010	8,058
Other income		(1,319)
Income (loss) from operations		9,412	7,393
Interest (expense) income allocation		(1,420)	(884)
Income (loss) before provision for income taxes		7,992	6,509
Rental equipment acquisitions		5,128	7,651
Accounts receivable, net (period end)		14,117	13,776
Rental equipment, at cost (period end)		240,517	211,215
Rental equipment, net book value (period end)		$ 220,811	$ 195,074
Utilization (period end)	[1]	68.80%	79.80%
Average utilization	[1]	69.80%	80.80%
TRS-RenTelco [Member]
Segment Reporting Information [Line Items]
Rental revenues		$ 25,429	$ 29,134
Rental related services revenues		724	880
Sales and other revenues		7,610	6,106
Total revenues		33,763	36,120
Depreciation of rental equipment		11,527	12,389
Gross profit		13,875	15,620
Selling and administrative expenses		8,918	9,451
Other income		(1,742)
Income (loss) from operations		6,699	6,169
Interest (expense) income allocation		(2,062)	(1,742)
Income (loss) before provision for income taxes		4,505	4,653
Rental equipment acquisitions		3,393	10,112
Accounts receivable, net (period end)		22,637	24,493
Rental equipment, at cost (period end)		370,641	401,801
Rental equipment, net book value (period end)		$ 133,766	$ 171,104
Utilization (period end)	[1]	56.80%	59.00%
Average utilization	[1]	56.50%	59.20%
Enviroplex [Member]
Segment Reporting Information [Line Items]
Sales and other revenues	[2]	$ 1,719	$ 941
Total revenues	[2]	1,719	941
Gross profit	[2]	445	125
Selling and administrative expenses	[2]	1,803	1,533
Income (loss) from operations	[2]	(1,358)	(1,408)
Interest (expense) income allocation	[2]	577	549
Income (loss) before provision for income taxes	[2]	(781)	(859)
Accounts receivable, net (period end)	[2]	$ 8,814	$ 3,633

[1] Utilization is calculated each month by dividing the cost of rental equipment on rent by the total cost of rental equipment, excluding accessory equipment, and new equipment inventory. The Average utilization for the period is calculated using the average costs of rental equipment.

[2] Gross Enviroplex sales revenues were $1,719 and $941 for the three months ended March 31, 2024 and 2023, respectively. There were no inter-segment sales to Mobile Modular in the three months ended March 31, 2024 and 2023, which required elimination in consolidation.