Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Basic earnings per share: [Abstract]
Net income (loss)		$ (17)	$ (98)
Net income (loss) available to common stockholders		$ (17)	$ (98)
Basic weighted average shares	[1]	85,554,236	88,131,373
Basic		$ (0.2)	$ (1.12)
Diluted earnings per share: [Abstract]
Net income (loss)		$ (17)	$ (98)
Less: Undistributed earnings allocated to participating securities		0	0
Net income (loss) available to common stockholders		$ (17)	$ (98)
Basic weighted average shares	[1]	85,554,236	88,131,373
Stock options		0	0
Warants		0	0
Diluted weighted average shares	[1]	85,554,236	88,131,373
Diluted		$ (0.2)	$ (1.12)
Unvested Restricted Stock And Units That Receive Nonforfeitable Dividends Or Dividend Equivalents That Have Met Service Condition		900,000	300,000
Potentially dilutive securities excluded from the diluted EPS because of antidilutive effect		4,500,000	13,700,000

[1] Includes 0.9 million and 0.3 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the three months ended March 31, 2019 and 2018, respectively.