Summary of Significant Accounting Policies - Credit loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Allowance activity
Allowance for doubtful accounts, beginning balance	$ 25	$ 33
Additions charged to expense	55	35
Accounts written-off, net of recoveries	(49)	(36)
Acquisitions, divestitures and other, net	(5)	(7)
Allowance for doubtful accounts, ending balance	26	25
Accounts receivable, net of allowance	$ 2,461	$ 2,278
Receivables outstanding less than 60 days (as a percent)	90.00%	90.00%
Threshold period to measure receivables	60 days	60 days
Receivables classified as current (as a percent)	0.55%	0.60%
Receivables related to income tax payments in excess of our provision for income taxes	$ 150	$ 166
Federal Fuel Credits Receivable	$ 19	$ 14