Equity-Based Compensation (Stock Options And Stock Appreciation Rights Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Equity-Based Compensation [Abstract]
Outstanding at beginning, shares	7,709	10,983	13,167
Outstanding at beginning, weighted average remaining contractual term, years	3.20
Exercised, shares	(1,028)	(297)
Exercised, weighted average exercise price	$ 40.52	$ 37.53
Forfeited or expired, shares	(2,246)	(1,887)
Forfeited or expired, weighted average exercise price	$ 50.06	$ 54.76
Outstanding at end, shares	7,709	10,983	13,167
Outstanding at end, weighted average exercise price	$ 53.37	$ 51.49	$ 51.64
Outstanding at end, weighted average remaining contractual term, years	3.20
Outstanding at end, aggregate intrinsic value	$ 10
Exercisable, shares	7,221
Exercisable, weighted average exercise price	$ 53.69
Exercisable, weighted average remaining contractual term, years	2.90
Exercisable, aggregate intrinsic value	$ 4