Summary of Preliminary Fair Value of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Apr. 30, 2018	Jan. 31, 2018	Dec. 15, 2017
Business Acquisition [Line Items]
Goodwill	$ 255,361	$ 255,361
IWCO
Business Acquisition [Line Items]
Accounts receivable			$ 47,841
Inventory			32,755
Other current assets			7,427
Property and equipment			87,976
Intangible assets			210,920
Goodwill			255,361
Other assets			3,040
Accounts payable			(31,069)
Accrued liabilities and other current liabilities			(59,799)
Customer deposits			(7,829)
Deferred income taxes			(75,775)
Other liabilities			(1,627)
Total consideration			469,221
Previously Reported
Business Acquisition [Line Items]
Goodwill		259,085
Previously Reported | IWCO
Business Acquisition [Line Items]
Accounts receivable			47,841
Inventory			27,165
Other current assets			7,427
Property and equipment			87,976
Intangible assets			210,920
Goodwill			259,085
Other assets			3,040
Accounts payable			(31,069)
Accrued liabilities and other current liabilities			(35,790)
Customer deposits			(7,829)
Deferred income taxes			(79,918)
Other liabilities			(19,627)
Total consideration			469,221
Adjustments
Business Acquisition [Line Items]
Goodwill		$ (3,724)
Adjustments | IWCO
Business Acquisition [Line Items]
Inventory			5,590
Goodwill			(3,724)
Accrued liabilities and other current liabilities			(24,009)
Deferred income taxes			4,143
Other liabilities			$ 18,000