Derivative and Financial Instruments (Commodity - Income Statement Location - Gain (Loss) Amounts of Derivatives) (Details) - Commodity Contract [Member] - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Sales and other operating revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) from commodity derivatives	$ (228,000,000)	$ 19,000,000	$ 141,000,000
Other Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) from commodity derivatives	25,000,000	4,000,000	4,000,000
Purchased commodities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) from commodity derivatives	$ 75,000,000	$ 11,000,000	$ (118,000,000)