Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States	$ 94	$ 16	$ 43
Other nations	93	88	75
States (U.S.)	27	20	9
Current income tax expense	214	124	127
United States	(61)	39	1,078
Other nations	(22)	(18)	(8)
States (U.S.)	(1)	(12)	30
Deferred income tax expense (benefit)	(84)	9	1,100
Total income tax expense	$ 130	$ 133	$ 1,227