Derivatives - Gains and Losses on Derivatives (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	$ (223)	$ (76)	$ 176	$ (661)
Collars and Call Options | Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	(166)	5	(238)	957
Marketing Derivatives | Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	22	(392)	202	18
Interest Rate Swaps | Gains (losses) on interest rate swaps and warrants, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	(223)	4	176	(665)
Other | Gains (losses) on interest rate swaps and warrants, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	$ 0	$ (79)	$ 0	$ 5