Consolidated Statements of Changes in Equity (USD $) In Millions, except Share data	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Loss	Non-controlling Interest	Stockholders' Equity, Total [Member]
Beginning Balance at Dec. 31, 2011	$ 7,053	$ 3,417	$ 3,750	$ (158)	$ 44	$ 7,053
Beginning Balance, shares at Dec. 31, 2011	169,247,282	169,247,000
Net Income	158		156			158
Net Income (Loss) Attributable to Noncontrolling Interest	2				2
Dividends declared on common stock			(100)			(100)
Stock Issued During Period, Shares, New Issues		180,000
Stock Issued During Period, Value, New Issues		10				10
Benefit obligations, net of tax	3			3		3
Net change in unrealized losses on investments, net of tax	1			1		1
Foreign currency translation, net of tax	1			1		1
Stock-based compensation, distributions to noncontrolling interests and other, shares		685,000
Stock-based compensation, distributions to noncontrolling interests and other		26				21
Stockholders' Equity, Other			(2)
Payments of Dividends, Noncontrolling Interest					(3)
Ending Balance at Mar. 31, 2012	$ 7,147	$ 3,453	$ 3,804	$ (153)	$ 43	$ 7,147
Ending Balance, shares at Mar. 31, 2012	170,112,217	170,112,000