Stock Option Plans (Stock Option Activity) (Details) (USD $)	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Stock Option Plans [Abstract]
Options Outstanding, Beginning Balance	7,329,820	8,056,327	8,387,994
Options Outstanding, Granted	900,073	965,050	1,082,979
Options Outstanding, Exercised	(1,008,848)	(1,607,081)	(1,379,827)
Options Outstanding, Canceled	(23,163)	(84,476)	(34,819)
Options Outstanding, Ending Balance	7,197,882	7,329,820	8,056,327
Weighted Average Exercise Price, Beginning Balance	$ 23.88	$ 20.97	$ 17.72
Weighted Average Exercise Price, Granted	$ 42.17	$ 33.91	$ 34.76
Weighted Average Exercise Price, Exercised	$ 18.80	$ 14.79	$ 11.90
Weighted Average Exercise Price, Canceled	$ 34.02	$ 33.94	$ 27.45
Weighted Average Exercise Price, Ending Balance	$ 26.84	$ 23.88	$ 20.97