Income Taxes (Schedule of Provision for Income Taxes for Income from Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal	$ 1		$ 5
State	(9)	$ 5	7
Total, Current	(8)	5	12
Deferred:
Federal	50	(485)	(88)
State	(53)	31	(28)
Total, Deferred	(3)	(454)	(116)
Total benefit from income taxes for loss from continuing operations	$ (11)	$ (449)	$ (104)