Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Accumulated other comprehensive loss
Foreign currency translation adjustment	$ (72)	$ (11)
Unrealized depreciation on investments, net of deferred income taxes of $0 and $(1) for December 31, 2011 and 2010, respectively	0	(2)
Accumulated other comprehensive income (loss)	(72)	(13)
Accumulated other comprehensive loss, deferred taxes
Unrealized appreciation (depreciation) on investments, deferred income taxes	$ 0	$ (1)