Contingent Liabilities and Commitments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015
Loss Contingencies [Line Items]
Standby Repurchase Obligations Amount	$ 1,898,307	$ 1,363,576
Term of Commitments	Up to eighteen months
Repurchase and guarantee reserve balances	$ 6,068	$ 4,163