Share-Based Compensation (Stock Option and SAR Activity) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at the beginning of the period	63
Granted, Shares	8
Exercised, Shares	(28)
Forfeited, Shares	(2)
Outstanding at the end of the period	41
Exercisable at end of period, Shares	30
Vested and expected to vest end of period, Shares	40
Outstanding at beginning of period, Weighted-Average Exercise Price	$ 45
Granted, Weighted-Average Exercise Price	$ 58
Exercised, Weighted-Average Exercise Price	$ 44
Forfeited, Weighted-Average Exercise Price	$ 55
Outstanding at end of period, Weighted-Average Exercise Price	$ 48
Exercisable at end of period, Weighted-Average Exercise Price	$ 46
Vested and expected to vest end of period, Weighted-Average Exercise Price	$ 48
Outstanding at end of period, Weighted Average Remaining Contractual Term (in years)	4 years 6 months
Exercisable at end of period, Weighted Average Remaining Contractual Term (in years)	3 years 1 month 6 days
Vested and expected to vest end of period, Weighted Average Remaining Contractual Term (in years)	4 years 6 months
Outstanding at end of period, Aggregate Intrinsic Value	$ 1,121
Exercisable at end of period, Aggregate Intrinsic Value	879
Vested and expected to vest end of period, Aggregate Intrinsic Value	$ 1,110