Implemented Accounting Pronouncements - Summary of Disaggregates the Company's Revenue by Lease and Non Lease (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation Of Revenue [Line Items]
Total revenues	$ 105,085	$ 94,837
Leasing [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	83,553	77,197
Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	9,882	9,288
Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	11,255	7,897
Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	395	455
Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	21,532	17,640
Mobile Modular [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	53,851	48,303
Mobile Modular [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	45,271	42,398
Mobile Modular [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	3,985	2,941
Mobile Modular [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	4,593	2,964
Mobile Modular [Member] | Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	2
Mobile Modular [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	8,580	5,905
TRS-RenTelco [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	28,038	25,314
TRS-RenTelco [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	22,499	20,216
TRS-RenTelco [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	807	658
TRS-RenTelco [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	4,339	3,985
TRS-RenTelco [Member] | Non-lease Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	393	455
TRS-RenTelco [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	5,539	5,098
Adler Tanks [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	21,178	20,461
Adler Tanks [Member] | Leasing [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	15,783	14,583
Adler Tanks [Member] | Non-lease Rental Related Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	5,090	5,689
Adler Tanks [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	305	189
Adler Tanks [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	5,395	5,878
Enviroplex [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	2,018	759
Enviroplex [Member] | Non-lease Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	2,018	759
Enviroplex [Member] | Non-lease Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	$ 2,018	$ 759