Commitments and Contingencies (Details) - USD ($)	12 Months Ended				48 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2015
Future Minimum Lease Payments, Net Of Subleases, Under Operating Leases
2016	$ 6,140,000				$ 6,140,000
2017	5,843,000				5,843,000
2018	5,365,000				5,365,000
2019	4,193,000				4,193,000
2020	3,187,000				3,187,000
Thereafter	10,164,000				10,164,000
Total	34,892,000				34,892,000
Lease Expense
Lease expense charged to operations	5,363,000	$ 5,171,000	$ 5,983,000
Employment change of control and indemnification agreement
Legal costs incurred by the Company in response to subpoenas			$ 500,000	$ 1,000,000	$ 1,500,000
Executive Chairman
Related Party Transactions
Related party lease payments made	$ 606,000
Lease expiration date	Dec. 31, 2021
Additional term of related party lease agreement as an option to exercise (in years)	10 years
Rent amount in next calendar year for related party lease agreement	$ 625,000