Earnings (Loss) Per Share (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Antidilutive securities excluded (in shares)	1,300,000	15,800,000
Numerator:
Net income (loss)	$ 13	$ (20)
Net income (loss) available to common shareholders	13	(20)
Denominator:
Denominator for basic earnings (loss) per share - weighted-average common shares (in shares)	63,131,000	60,850,000
Denominator for diluted earnings (loss) per share—adjusted weighted-average common shares (in shares)	76,266,000	60,850,000
Basic earnings (loss) per share (in dollars per share)	$ 0.21	$ (0.34)
Diluted earnings (loss) per share (in dollars per share)	$ 0.17	$ (0.34)
Employee stock options and warrants
Denominator:
Employee stock options and warrants (in shares)	709,000	0
Convertible debt interest - 1 7/8 percent notes [Member]
Numerator:
Convertible debt interest - 1 7/8 percent notes	$ 0	$ 0
Denominator:
Convertible subordinated notes (in shares)	1,015,000	0
Convertible subordinated notes - 4 percent
Denominator:
Convertible subordinated notes (in shares)	10,794,000	0
Restricted stock units
Denominator:
Employee stock options and warrants (in shares)	617,000	0