Contingent Liabilities Commitments and Legal Matters - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2015	Jul. 31, 2015
Loss Contingencies [Line Items]
Standby Repurchase Obligations Amount	$ 1,313,093	$ 1,363,576
Term of Commitments	Up to eighteen months
Repurchase and guarantee reserve balances	$ 4,010	$ 4,163

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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