Discontinued Operations - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Oct. 21, 2013	Feb. 28, 2014	Jul. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of bus business	$ 100,000		$ 105,043
Discontinued operation, amounts collected from ASV		$ 5,043
Pre-tax gain (loss) on disposal of discontinued business			7,079
Impact of indemnification to tax expenses			$ 1,883