Income Taxes - Schedule of Components of Income Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended																12 Months Ended
	Dec. 31, 2019	[1]	Sep. 30, 2019	[1]	Jun. 30, 2019	[1]	Mar. 31, 2019	[1]	Dec. 31, 2018	[1]	Sep. 30, 2018	[1]	Jun. 30, 2018	[1]	Mar. 31, 2018	[1]	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. income before tax																	$ 234		$ 380		$ 283
Foreign income before tax																	39		23		28
Income before income taxes	$ 74		$ 70		$ 54		$ 75		$ 161		$ 56		$ 146		$ 40		$ 273	[1]	$ 403	[1]	$ 311

[1] The sum of the earnings per share for the four quarters may differ from annual earnings per share due to the required method of computing the weighted average shares in interim periods.