Income Taxes - Schedule of Components of Provision for Income Tax Expense (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal		$ 37	$ 62	$ 94
State		9	15	11
Foreign		8	8	8
Total current		54	85	113
Deferred:
Federal		3	17	(137)
State		1	4	8
Foreign		(1)	(1)
Total deferred		3	20	(129)
Total provision for income taxes	[1]	$ 57	$ 105	$ (16)

[1] On December 22, 2017, the United States enacted tax reform legislation, the TCJ Act, resulting in significant modifications to existing law which resulted in a reduction in income tax expense for the year ended December 31, 2017. See Note 17: Income Taxes for additional information.