Subsequent Events Subsequent Events (Details) - USD ($) $ in Millions	3 Months Ended						12 Months Ended
	Oct. 31, 2016	Jul. 31, 2016	Jul. 31, 2015	Apr. 30, 2015	Oct. 31, 2014	Oct. 31, 2013	Jul. 31, 2016
Subsequent Event [Line Items]
Exercise of stock options, net of repurchased shares (in shares)		1,130,000	200,000	139,690	201,333	14,000
Shares Paid for Tax Withholding for Share Based Compensation		426,200	81,240	43,013	41,296	4,240
Amortization of Debt Issuance Costs, Subsequent Events							$ 0.6
Subsequent Event [Member]
Subsequent Event [Line Items]
Exercise of stock options, net of repurchased shares (in shares)	9,000,000
Shares Paid for Tax Withholding for Share Based Compensation	3,667,853
Second Amendment To Credit Agreement [Member] [Domain] | Revolving Credit Facility [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from Lines of Credit	$ 135.0