CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (UNAUDITED) (USD $) In Millions, except Share data, unless otherwise specified		Total	Common Stock		Additional Paid-In Capital	(Accumulated Deficit) Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2013		$ 1,828	$ 1		$ 2,054	$ (37)	$ (209)	$ 19	[1]
Balance (in shares) at Dec. 31, 2013		93,288,936	93,288,936	[2]			4,677,866
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		60				60
Foreign currency translation adjustments		(38)						(38)	[1]
Fixed price diesel swaps		(1)						(1)	[1]
Stock compensation expense, net					12
Exercise of common stock options					1
4 percent Convertible Senior Notes (in shares)	[2],[3]		5,000,000
4 percent Convertible Senior Notes	[3]				12
Shares repurchased and retired					(18)
Repurchase of common stock							(43)
Balance at Mar. 31, 2014		$ 1,813	$ 1		$ 2,061	$ 23	$ (252)	$ (20)	[1]
Balance (in shares) at Mar. 31, 2014		97,527,696	97,527,696	[2]			5,180,203

[1] The Accumulated Other Comprehensive Income (Loss) balance primarily reflects foreign currency translation adjustments.

[2] An aggregate of less than 1 million net shares were issued during the year ended December 31, 2013.

[3] Reflects amortization of the original issue discount on the 4 percent Convertible Senior Notes (an amount equal to the unamortized portion of the original issue discount is reflected as “temporary equity” in our consolidated balance sheet) and the conversion of a portion of the 4 percent Convertible Senior Notes during the three months ended March 31, 2014, net of cash received from the option counterparties to our convertible note hedges upon the conversion. See note 6 to our condensed consolidated financial statements for additional detail.