Stock Compensation Plans and Other Compensation Arrangements (Details 2) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Stock Option Activity (Table)
Shares under option - outstanding at period start	6,271
Shares under option - exercised	(4,522)
Shares under option - cancelled and forfeited	(29)
Shares under option - outstanding at period end	1,720	6,271
Stock Options, Weighted Average Exercise Price (Table)
Weighted-average exercise price - outstanding at period start	$ 58
Weighted-average exercise price - exercised	$ 59
Weighted-average exercise price - cancelled and forfeited	$ 60
Weighted-average exercise price - outstanding at period end	$ 56	$ 58
Exercisable at Period End [Table]
Shares under option - exercisable at period end	1,343
Weighted-average exercise price - exercisable at period end	$ 55
Weighted-average remaining contractual term - exercisable at period end	2 years 2 months
Aggregate intrinsic value - exercisable at period end	$ 80
Stock Options, Vested and Expected to Vest at Period End [Table]
Shares under option - vested and expected to vest in the future at period end	1,716
Weighted-average exercise price - vested and expected to vest in the future at period end	$ 56
Weighted-average remaining contractual term - vested and expected to vest in the future at period end	2 years 7 months
Aggregate intrinsic value - vested and expected to vest in the future at period end	101
Weighted-average remaining contractual term - outstanding at period end	2 years 7 months	2 years 11 months
Aggregate intrinsic value - outstanding at period end	$ 101	$ 66