Income Taxes (Schedule of Provision for Income Taxes for Income from Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 5	$ 7	$ (29)
State	7	7	3
Total, Current	12	14	(26)
Deferred:
Federal	(88)	103	106
State	(28)	(1)	2
Total, Deferred	(116)	102	108
Total (benefit from) provision for income taxes for (loss) income from continuing operations	$ (104)	$ 116	$ 82