Shareholders' Equity (Details 1) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, Beginning balance	6,608,614
Granted	1,047,375
Exercised	(1,262,313)
Forfeited/Cancelled	(9,877)
Options outstanding, Ending balance	6,383,799	6,608,614
Options exercisable	3,465,644
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Average exercise price, Beginning balance	$ 32.16
Average exercise price, Granted	$ 56.47	$ 44.01	$ 38.10
Average exercise price, Exercised	$ 28.19
Average exercise price, Forfeited/Cancelled	$ 42.22
Average exercise price, Ending balance	$ 36.92	$ 32.16
Average exercise price, Options exercisable	$ 30.04
Average remaining contractual term, Options outstanding	5 years 9 months 18 days
Average remaining contractual term, Options exercisable	4 years 1 month 6 days
Aggregate intrinsic value, Options outstanding	$ 152
Aggregate intrinsic value, Options exercisable	$ 106