Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Comprehensive Income [Line Items]
Net Unrealized Gain/(Loss) on Derivaive	$ (4)	$ (4)
Net Unrealized Gain/(Loss) on Investments	(30)	(30)
Benefit Obligations	(125)	(116)
Foreign Currency Translation	1	1
Accumulated Other Comprehensive Loss	(158)	(149)
Current period change, net of tax Net Unrealized Gain/(Loss) on Derivatives Gain (Loss) on Derivatives Arising During Period, Net of Tax	0	1	3
Current period change, net of tax Net Unrealized Gain/(Loss) on Investments	0	(20)	8
Current period change, net of tax Benefit Obligations	(9)	15	7
Current period change, net of tax Foreign Currency Translation	0	1	2
Current period change, net of tax AccumulatedOther Comprehensive Loss	$ (9)