Income Taxes (Reconciliation Of Effective Income Tax Rate And Effective Rate From Continuing Operation) (Details)	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Income Tax Disclosure [Abstract]
Current Fiscal Year End Date	--07-31
At U.S. Federal income tax rate	35.00%	35.00%	35.00%
State income tax, net of Federal benefit	3.10%	3.20%	3.40%
Nondeductible meals or entertainment	0.10%	0.20%	0.70%
General business credits	(0.40%)	(0.50%)	(1.70%)
Effective Income Tax Rate Reconciliation, Tax Settlement, Other, Amount	0.00%	(16.00%)	0.00%
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	0.10%	0.50%	0.00%
Effective Income Tax Rate Reconciliation, Domestic Production Deduction	(0.40%)	(0.70%)	(1.40%)
Other	0.90%	1.50%	0.00%
Effective income tax rate	38.40%	23.20%	36.00%