Contingent Liabilities and Commitments and Legal Matters - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Apr. 30, 2015	Jul. 31, 2014
Loss Contingencies [Line Items]
Standby Repurchase Obligations Amount	$ 1,576,439	$ 1,226,650
Term of Commitments	Up to eighteen months
Repurchase and guarantee reserve balances	$ 4,942	$ 3,948

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

No definition available.

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