Contingent Liabilities, Commitments and Legal Matters (Detail) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2019	Jul. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Standby repurchase obligations amount	$ 2,848,310	$ 2,961,019
Term of commitments	up to eighteen months
Repurchase and guarantee reserve balances	$ 8,888	$ 9,575

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

No definition available.

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Period Type:	duration