Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Cash paid for income taxes, net of refunds	$ 319	$ 560	$ 176
Cash paid for interest	86	150	145
Beginning restricted cash	4	7	17
Ending restricted cash	$ 4	$ 4	$ 7