Revenue Recognition - Summary of Disaggregates the Company's Revenue by Lease and Non Lease (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019		Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Leasing revenues		$ 107,200		$ 304,200
Total non-lease revenues				84,613		$ 70,735
Total revenues		173,562	$ 143,147	423,009		365,215
Leasing [Member]
Disaggregation Of Revenue [Line Items]
Leasing revenues		107,215	94,184	304,154		267,744
Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		16,039	13,120	38,369		30,716
Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		49,791	35,364	78,877		65,333
Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		517	479	1,609		1,422
Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		66,347	48,963	118,855		97,471
Mobile Modular [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues				32,434		31,667
Total revenues		86,302	74,891	219,116		188,613
Mobile Modular [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Leasing revenues		61,519	52,036	171,995		146,672
Mobile Modular [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		8,105	5,697	15,651		11,226
Mobile Modular [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		16,676	17,140	31,401		30,694
Mobile Modular [Member] | Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		2	18	69		21
Mobile Modular [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		24,783	22,855	47,121		41,941
TRS-RenTelco [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues				18,601		18,321
Total revenues		34,090	28,137	97,076		86,527
TRS-RenTelco [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Leasing revenues		28,284	23,206	79,450		69,183
TRS-RenTelco [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		717	642	1,958		1,816
TRS-RenTelco [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		4,614	3,828	14,235		14,179
TRS-RenTelco [Member] | Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		475	461	1,433		1,349
TRS-RenTelco [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		5,806	4,931	17,626		17,344
Adler Tanks [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues				1,340		916
Total revenues		24,809	26,017	74,579		70,244
Adler Tanks [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Leasing revenues		17,412	18,942	52,709		51,889
Adler Tanks [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		7,217	6,781	20,760		17,674
Adler Tanks [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		140	294	1,003		629
Adler Tanks [Member] | Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		40		107		52
Adler Tanks [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		7,397	7,075	21,870		18,355
Enviroplex [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues	[1]			32,238		19,831
Total revenues		28,361	14,102	32,238	[1]	19,831	[1]
Enviroplex [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		28,361	14,102	32,238		19,831
Enviroplex [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total non-lease revenues		$ 28,361	$ 14,102	$ 32,238		$ 19,831

[1] Gross Enviroplex sales revenues were $32,238 and $21,191 for the nine months ended September 30, 2019 and 2018, respectively. There were $1,360 inter-segment sales to Mobile Modular in the nine months ended September 30, 2018, which required elimination in consolidation.  There were no inter-segment sales in the nine months ended September 30, 2019.