Other Noncurrent Liabilities - Other Noncurrent Liabilities (Details) - USD ($) $ in Millions		Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Reserve for underground storage tank removal		$ 67		$ 54	$ 41
Accrued environmental expense, long-term		23		29
Unfavorable lease liability	[1]	0		16
Other		7		24
Other noncurrent liabilities		$ 97	$ 111	$ 123

[1] As a part of ASC 842, unfavorable lease liabilities were reclassed to adjust the operating lease right-of-use asset.