Income Taxes (Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal	$ (2)	$ 0	$ (10)
State	2	20	18
Foreign	3	(3)	(14)
Total current	3	17	(6)
Federal	66	(1)	5
State	28	(6)	6
Foreign	1	54	3
Total deferred	95	47	14
Total income tax expense (benefit)	$ 98	$ 64	$ 8