Components of Amortizable Intangible Assets, Net (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2017	Jul. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Cost	$ 572,827	$ 588,327
Accumulated Amortization	$ 98,930	80,936
Dealer Network/Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	16 years
Cost	$ 404,960	404,960
Accumulated Amortization	$ 75,890	55,191
Trademarks
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	19 years
Cost	$ 148,117	148,117
Accumulated Amortization	$ 14,305	10,539
Design Technology And Other Intangibles
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	8 years
Cost	$ 19,300	22,400
Accumulated Amortization	$ 8,487	10,870
Non-Compete Agreements
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	2 years
Cost	$ 450	450
Accumulated Amortization	$ 248	203
Backlog
Finite-Lived Intangible Assets [Line Items]
Cost		12,400
Accumulated Amortization		$ 4,133