Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory U.S. federal income tax provision	$ (59)	$ 57	$ 85
State and local income taxes, net of U.S. federal tax benefit	(17)	11	19
Impact of foreign operations	(5)	1	2
Interest on installment sales, net of U.S. federal tax benefit	1	4	3
Effects of the TCJ Act			(4)
Tax accounting method change		(18)
Other	1	2
Total provision for income taxes	$ (79)	$ 57	$ 105