Stock Option Plans (Stock Option Activity) (Details) (USD $)	12 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Stock Option Plans [Abstract]
Options Outstanding, Beginning Balance	8,056,327	8,387,994	9,543,624
Options Outstanding, Granted	965,050	1,082,979	1,103,202
Options Outstanding, Exercised	(1,607,081)	(1,379,827)	(2,243,502)
Options Outstanding, Canceled	(84,476)	(34,819)	(15,330)
Options Outstanding, Ending Balance	7,329,820	8,056,327	8,387,994
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 20.97	$ 17.72	$ 15.02
Weighted Average Exercise Price, Granted	$ 33.91	$ 34.76	$ 28.61
Weighted Average Exercise Price, Exercised	$ 14.79	$ 11.90	$ 11.55
Weighted Average Exercise Price, Canceled	$ 33.94	$ 27.45	$ 23.60
Weighted Average Exercise Price, Outstanding, Ending Balance	$ 23.88	$ 20.97	$ 17.72