Income Taxes Schedule of Components of Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ 6	$ 9	$ 12
State and local	17	12	22
Current Income Tax Expense (Benefit)	23	21	34
Deferred:
Federal	(22)	(2)	(15)
State and local	(1)	8	(2)
deferred income tax expense	(23)	6	(17)
Income tax expense	$ 0	$ 27	$ 17