Earnings Per Share (Computation Of Basic And Diluted EPS) (Details) (USD $) In Millions, except Per Share data	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Earnings Per Share
Net income	$ 175		$ 156		$ 361		$ 300
Basic weighted average shares outstanding	159		177		166		179
Stock options, SSARs and RSUs	3	[1]	4	[1]	3	[1]	4	[1]
Warrants			3	[2]	1	[2]	3	[2]
Diluted weighted average shares outstanding	162		184		170		186
Earnings per share
Basic	$ 1.10		$ 0.88		$ 2.17		$ 1.68
Diluted	$ 1.08		$ 0.84		$ 2.12		$ 1.62

[1] Includes unvested dilutive restricted stock units ("RSUs") which are subject to future forfeitures.

[2] Represents the dilutive effect of warrants to purchase shares of the Company's common stock related to the May 2009 issuance of the Company's convertible notes (see Note 7—Long-Term Debt and Borrowing Arrangements).