Share-Based Compensation (Stock Option Activity) (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2011 years		Sep. 30, 2010
Share-Based Compensation [Abstract]
Stock Options Outstanding, Beginning of Period	10,112,842
Stock Options, Grants	1,267,430	[1]
Stock Options, Exercised	(926,171)
Stock Options, Forfeited or Expired	(380,208)
Stock Options Outstanding, End of Period	10,073,893
Stock Options, Exercisable	5,312,827		5,900,000
Weighted Average Exercise Price, Beginning of Period	$ 16.92
Weighted Average Exercise Price, Grants	$ 25.28	[1]
Weighted Average Exercise Price, Exercised	$ 9.35
Weighted Average Exercise Price, Forfeited or Expired	$ 26.73
Weighted Average Exercise Price, End of Period	$ 18.30
Weighted Average Exercise Price, Exercisable	$ 13.85		$ 10.99
Weighted Average Remaining Contractual Term, Outstanding, Beginning of Period (in years)	5.7
Weighted Average Remaining Contractual Term, Outstanding, End of Period (in years)	5.7
Weighted Average Remaining Contractual Term, Exercisable (in years)	3.4
Aggregate Intrinsic Value, Outstanding, Beginning of Period	$ 89
Aggregate Intrinsic Value, Outstanding, End of Period	71
Aggregate Intrinsic Value, Exercisable	$ 64

[1] Primarily reflects our company-wide equity grant issued in March 2011, which includes a performance-based accelerated vesting feature based on achievement of specific levels of corporate performance, as described above.