Acquisitions - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Apr. 01, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill	$ 105,843			$ 31,197	$ 31,197
CEC [Member]
Business Acquisition [Line Items]
Cash			$ 1,244
Accounts receivable			7,583
Inventory			504
Prepaid expenses and other assets			324
Rental equipment			55,342
Property and equipment			2,700
Intangible assets			21,500
Total identifiable assets acquired			89,197
Accounts payable			(1,023)
Accrued expenses payable and other liabilities			(876)
Total liabilities assumed			(1,899)
Net identifiable assets acquired			87,298
Goodwill			45,092
Net assets acquired			$ 132,390
Rental Inc [Member]
Business Acquisition [Line Items]
Cash		$ 260
Accounts receivable		2,873
Inventory		5,324
Prepaid expenses and other assets		47
Rental equipment		22,578
Property and equipment		1,935
Intangible assets		10,200
Total identifiable assets acquired		43,217
Accounts payable		(439)
Manufacturer flooring plans payable		(3,293)
Accrued expenses payable and other liabilities		(469)
Total liabilities assumed		(4,201)
Net identifiable assets acquired		39,016
Goodwill		29,554
Net assets acquired		$ 68,570