Stock-Based Compensation (Stock Options Granted and Outstanding) (Details) (USD $)					12 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2012	May 31, 2011	May 31, 2014 Stock Options [Member]	May 31, 2013 Stock Options [Member]	May 31, 2012 Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning of period (shares)					7,885,638	7,609,117	7,664,703
Granted (shares)					2,111,649	1,722,081	1,638,907
Canceled (shares)					(699,314)	(884,384)	(1,591,480)
Exercised (shares)					(1,272,179)	(561,176)	(103,013)
Outstanding, end of period (shares)					8,025,794	7,885,638	7,609,117
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding, begining of period, Weighted Average Exercise Price (dollars per share)					$ 37.60	$ 36.04	$ 36.12
Granted, Weighted Average Exercise Price (dollars per share)					$ 61.04	$ 44.67	$ 36.26
Canceled, Weighted Average Exercise Price (dollars per share)					$ 42.42	$ 38.69	$ 36.90
Exercised, Weighted Average Exercise Price (dollars per share)					$ 39.03	$ 36.44	$ 32.66
Outstanding, end of period, Weighted Average Exercise Price (dollars per share)					$ 43.12	$ 37.60	$ 36.04
Number of exercisable options (shares)	1,583,413	1,815,795	2,105,702	1,945,207