Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Basic earnings per share: [Abstract]
Net income (loss)	$ 250		$ 1,234		$ (1,319)
Less: Undistributed earnings allocated to participating securities	5		32		0
Net income (loss) available to common stockholders	245		1,202	[1]	(1,319)
Basic weighted average shares	189,071,011	[2]	188,834,626	[1],[2]	192,505,045	[1],[2]
Net income (loss) per basic common share	$ 1.30		$ 6.36		$ (6.85)	[1]
Diluted earnings per share: [Abstract]
Net income (loss)	250		1,234		(1,319)
Less: Undistributed earnings allocated to participating securities	5		32		0
Less: mark-to-market gain (loss) on warrants	0		0		0
Net income (loss) available to common stockholders	$ 245		$ 1,202	[1]	$ (1,319)
Basic weighted average shares	189,071,011	[2]	188,834,626	[1],[2]	192,505,045	[1],[2]
Stock options	1,241,902		1,062,395		0
Warants	0		0		0
Diluted weighted average shares	190,312,913		189,897,021	[1]	192,505,045	[1]
Net income (loss) per diluted common share	$ 1.29		$ 6.33		$ (6.85)	[1]
Unvested Restricted Stock And Units That Receive Nonforfeitable Dividends Or Dividend Equivalents That Have Met Service Condition	629,896		506,714		565,819

[1] Amounts shown are revised.

[2] Includes 629,896, 506,714 and 565,819 of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the years ended December 31, 2013, 2012 and 2011, respectively.