Stock-Based Compensation Service-Based Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Oct. 31, 2017	Oct. 31, 2016
Service-Based Stock Options [Abstract]
Options Outstanding at July 31, 2016	2,879,801
Options Outstanding at July 31, 2016, Weighted Average Exercise Price	$ 27.40
Options, Grants in Period	364,046
Options, Grants in Period, Weighted Average Exercise Price	$ 36.85	$ 35.14
Options, Exercised in Period	(140,998)
Options, Exercises in Period, Weighted Average Exercise Price	$ 0
Options, Forfeitures or Expirations in Period	(10,719)
Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 27.14
Options Outstanding, Weighted Average Remaining Contractual Term	6 years 2 months 12 days
Options Outstanding at October 31, 2016	3,092,130
Options Outstanding at October 31, 2016, Weighted Average Exercise Price	$ 28.49
Options Outstanding, Aggregate Intrinsic Value	$ 29,020
Options Exercisable	2,229,350	2,616,609
Options Exercisable, Weighted Average Exercise Price	$ 27.39	$ 29.31
Options Exercisable, Weighted Average Remaining Contractual Term	5 years 1 month 6 days
Options Exercisable, Aggregate Intrinsic Value	$ 23,397