Stock-Based Compensation Service-Based Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Oct. 31, 2016	Oct. 31, 2015
Service-Based Stock Options [Abstract]
Options Outstanding at July 31, 2016	3,708,706
Options Outstanding at July 31, 2016, Weighted Average Exercise Price	$ 27.33
Options, Grants in Period	376,924
Options, Grants in Period, Weighted Average Exercise Price	$ 35.14	$ 19.97
Options, Exercised in Period	(337,300)
Options, Exercises in Period, Weighted Average Exercise Price	$ 0
Options, Forfeitures or Expirations in Period	(51,548)
Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 25.23
Options Outstanding, Weighted Average Remaining Contractual Term	5 years 10 months 24 days
Options Outstanding at October 31, 2016	3,696,782
Options Outstanding at October 31, 2016, Weighted Average Exercise Price	$ 28.26
Options Outstanding, Aggregate Intrinsic Value	$ 20,600
Options Exercisable	2,616,609	2,923,276
Options Exercisable, Weighted Average Exercise Price	$ 29.31	$ 30.32
Options Exercisable, Weighted Average Remaining Contractual Term	4 years 6 months
Options Exercisable, Aggregate Intrinsic Value	$ 12,069