Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Reserves deducted from deferred income taxes, net:
Valuation allowance, Beginning balance	$ 50,191	$ 50,797	$ 49,982
Valuation allowance, Additions charged to costs and expenses	3,500		$ 815
Valuation allowance, Deductions	(10)	$ (606)
Valuation allowance, Ending balance	$ 53,681	$ 50,191	$ 50,797