Earnings Per Share (Schedule Of Basic And Diluted Earnings Per Share) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Stock options outstanding, antidilutive	3,402,805		3,797,548		4,526,442
Net income (loss)	$ 1,234		$ (1,319)		$ 53
Basic weighted-average shares	193,842,435	[1]	197,019,968	[1]	202,421,433	[1]
Effect of common stock equivalents: Stock options	1,062,395				599,701
Diluted weighted-average shares	194,904,830		197,019,968		203,021,134
Basic	$ 6.36		$ (6.69)		$ 0.26
Diluted	$ 6.33		$ (6.69)		$ 0.26
Unvested restricted stock and units that receive nonforfeitable dividends or dividend equivalents	5,514,523		5,080,742		5,325,428

[1] Includes 5,514,523, 5,080,742 and 5,325,428 of unvested restricted stock and units that receive nonforfeitable dividends or dividend equivalents for the years ended December 31, 2012, 2011 and 2010, respectively.