Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss [Abstract]
Trade customers	$ 1,007	$ 948
Related parties	5	12
Allowance for credit losses	(23)	(22)
Accounts receivable from trade customers, net	989	938
Federal and state taxes	233	59
Other	43	39
Accounts receivable, net	$ 1,265	$ 1,036