Schedule of Major Classifications of Inventories (Detail) - USD ($) $ in Thousands	Jan. 31, 2017	Jul. 31, 2016
Inventory [Line Items]
Work in process	$ 128,501	$ 97,872
Raw materials	200,508	173,362
Chassis	102,979	102,686
Total	508,133	434,004
Excess of FIFO costs over LIFO costs	(30,535)	(30,135)
Total inventories, net	477,598	403,869
Recreational vehicles
Inventory [Line Items]
Finished goods	51,610	39,943
Other
Inventory [Line Items]
Finished goods	$ 24,535	$ 20,141