Divestiture Activities - Additional Information (Detail) - USD ($) $ in Millions	Feb. 21, 2019	Dec. 21, 2018	Jul. 31, 2019
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Property, plant and equipment, net			$ 0.2
Inventories, net			17.1
Accounts receivable, net			0.5
Other current and long-term assets			3.8
Accounts payable			12.8
Other current and long-term liabilities			$ 3.8
Mobility Van Business [Member] | Commercial Segment [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Annual sales of discontinued operation		$ 40.0
Regional Technical Center [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business	$ 11.4
Gain on sale of business	$ 1.2