Contingent Liabilities and Commitments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Oct. 31, 2014	Jul. 31, 2014
Loss Contingencies [Line Items]
Standby Repurchase Obligations Amount	$ 1,239,808
Term of Commitments	Up to eighteen months
Repurchase and guarantee reserve balances	$ 4,347	$ 3,948

Terms of commitments under repurchase agreements for the repurchase of products sold to dealers.

No definition available.

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Balance Type:	na
Period Type:	duration