Contingent Liabilities and Commitments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2019	Jul. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Standby repurchase obligations amount	$ 2,961,019	$ 2,748,465
Term of commitments	up to eighteen months.
Repurchase and guarantee reserve balances	$ 9,575	$ 7,400
EHG [Member]
Commitments and Contingencies Disclosure [Abstract]
Standby repurchase obligations amount	$ 755,852