Contingent Liabilities And Commitments (Principal Commercial Commitments Under Repurchase Agreements And Guarantees) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Apr. 30, 2012
Guarantee On Dealer Inventory Financing [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Total Amount Committed	$ 962
Terms of Commitments	Various
Standby Repurchase Obligations On Dealer Inventory Financing [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Total Amount Committed	$ 938,140
Terms of Commitments	Up to eighteen months