Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Discontinued operations components of earnings and balance sheet disclosure
Income (loss) from discontinued operations, net of tax	$ (1)	$ 2	$ (3)	$ (73)
Discontinued operations
Discontinued operations components of earnings and balance sheet disclosure
Total net revenues		102		342
Income (loss) from discontinued operations		2		(117)
Reduction of gain on sale	(1)		(4)
Income tax expense (benefit)			(1)	(44)
Income (loss) from discontinued operations, net of tax	$ (1)	$ 2	$ (3)	$ (73)