Contingent Liabilities And Commitments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Jun. 01, 2012	Jul. 31, 2012 LegalMatter	Jul. 31, 2011
Loss Contingencies [Line Items]
Repurchase and guarantee reserve balances		$ 3,150	$ 3,479
Chassis delivered to customers in days		90 days
Chassis consigned inventory		21,507
Additional chassis provided by customers		9,762
Suits currently pending		500
Payments for the benefit of settlement class	4,700	6,250
Heartland Recreational Vehicles, LLC,
Loss Contingencies [Line Items]
Payments for the benefit of settlement class		$ 553
Multidistrict Litigation Court
Loss Contingencies [Line Items]
Suits currently pending		4,100