Derivatives - Gains and Losses on Derivatives (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	$ 399	$ (585)
Collars and Call Options | Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	(72)	952
Marketing Derivatives | Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	180	410
Interest Rate Swaps | Gains (losses) on interest rate swaps and warrants, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	399	(669)
Other | Gains (losses) on interest rate swaps and warrants, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instrument	$ 0	$ 84