CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance at Dec. 31, 2010	$ 1,578	$ 1	$ 1,069	$ 465	$ 29	$ 14
Balance (in shares) at Dec. 31, 2010		55,699,218
Increase (Decrease) in Stockholders' Equity
Total comprehensive income	56			49	4	3
Distributions to noncontrolling interest	(5)					(5)
Stock compensation expense	2		2
Stock issued under share-based payment plans	6		6
Stock issued under share-based payment plans (in shares)		510,564
Balance at Mar. 31, 2011	1,637	1	1,077	514	33	12
Balance (in shares) at Mar. 31, 2011		56,209,782
Balance at Dec. 31, 2011	1,461	1	1,082	338	21	19
Balance (in shares) at Dec. 31, 2011	56,361,155	56,361,155
Increase (Decrease) in Stockholders' Equity
Total comprehensive income	89			75	4	10
Distributions to noncontrolling interest	(14)					(14)
Stock compensation expense	1		1
Stock issued under share-based payment plans	(2)		(2)
Stock issued under share-based payment plans (in shares)		284,578
Conversion option related to Convertible note issuance, net (Note 7)	33		33
Recognition of deferred taxes related to Convertible notes	1		1
Balance at Mar. 31, 2012	$ 1,569	$ 1	$ 1,115	$ 413	$ 25	$ 15
Balance (in shares) at Mar. 31, 2012	56,645,733	56,645,733