Stock-Based Compensation (Details) - Stock Option [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Stock Options
Stock options outstanding, Beginning balance	99,801	14,023	26,548
Stock options, Granted		87,707
Stock options, Exercised	(41,114)	(1,631)	(12,053)
Stock options, Cancelled/Forfeited	(179)	(298)	(472)
Stock options outstanding, Ending balance	58,508	99,801	14,023
Stock options, Vested and expected to vest	58,508
Stock options, Exercisable	52,828
Weighted- average Exercise Price
Weighted- average exercise price outstanding, Beginning balance	$ 44.63	$ 5.67	$ 5.67
Weighted- average exercise price outstanding, Granted		50.00
Weighted- average exercise price outstanding, Exercised	43.82	5.67	5.67
Weighted- average exercise price outstanding, Cancelled/Forfeited	5.67	5.67	5.67
Weighted- average exercise price outstanding, Ending balance	45.32	$ 44.63	$ 5.67
Weighted- average exercise price outstanding, Vested and expected to vest	45.32
Weighted- average exercise price outstanding, Exercisable	$ 49.58
Weighted- average Remaining Contractual Term (in years)
Weighted- average remaining contractual term, beginning balance, Outstanding	3 years 1 month 6 days	5 years 4 months 24 days	5 years 8 months 12 days
Weighted- average remaining contractual term, ending balance, Outstanding	2 years 1 month 6 days	3 years 1 month 6 days	5 years 4 months 24 days
Weighted- average remaining contractual term, Vested and expected to vest	2 years 1 month 6 days
Weighted- average remaining contractual term, Exercisable	1 year 10 months 25 days
Aggregate Intrinsic Value
Aggregate intrinsic value, Outstanding, beginning balance	$ 152	$ 251	$ 112
Aggregate intrinsic value, Outstanding, ending balance	7,845	$ 152	$ 251
Aggregate intrinsic value, Vested and expected to vest	7,845
Aggregate intrinsic value, Exercisable	$ 6,858