Schedule of Fair Value of Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	$ 44	$ 7
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0
Fair Value, Inputs, Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	747	338
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(539)	(165)
Derivative Asset	208	173
Derivative Liability, Fair Value, Gross Liability	937	521
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(565)	(171)
Derivative Liability	372	350
Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	709	219
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(518)	(139)
Derivative Asset	191	80
Derivative Liability, Fair Value, Gross Liability	700	299
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(544)	(143)
Derivative Liability	156	156
Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	38	119
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(21)	(26)
Derivative Asset	17	93
Derivative Liability, Fair Value, Gross Liability	237	222
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(21)	(28)
Derivative Liability	216	194
Other Current Assets [Member] \| Interest Rate Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	177	3
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(177)	(3)
Derivative Asset	0	0
Other Current Assets [Member] \| Foreign Exchange Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	39	39
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(25)	(19)
Derivative Asset	14	20
Other Current Assets [Member] \| Foreign Exchange Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	19	74
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(16)	(25)
Derivative Asset	3	49
Other Current Assets [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	409	146
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(274)	(109)
Derivative Asset	135	37
Other Current Assets [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	18	4
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(4)	(1)
Derivative Asset	14	3
Deferred charges and other assets [Member] \| Interest Rate Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	1	41
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(1)	0
Derivative Asset	0	41
Deferred charges and other assets [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	84	31
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(42)	(8)
Derivative Asset	42	23
Accrued and Other Current Liabilities [Member] \| Interest Rate Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		7
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset		(3)
Derivative Liability		4
Accrued and Other Current Liabilities [Member] \| Foreign Exchange Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	28	93
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(25)	(19)
Derivative Liability	3	74
Accrued and Other Current Liabilities [Member] \| Foreign Exchange Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	77	35
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(16)	(25)
Derivative Liability	61	10
Accrued and Other Current Liabilities [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	376	151
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(296)	(112)
Derivative Liability	80	39
Accrued and Other Current Liabilities [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	31	9
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(4)	(3)
Derivative Liability	27	6
Other Noncurrent Obligations [Member] \| Interest Rate Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	235
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(177)
Derivative Liability	58
Other Noncurrent Obligations [Member] \| Interest Rate Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	129
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(1)
Derivative Liability	128
Other Noncurrent Obligations [Member] \| Commodity Contract [Member] \| Fair Value, Inputs, Level 2 [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	61	48
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(46)	(9)
Derivative Liability	$ 15	39
Other Noncurrent Obligations [Member] \| Interest Rate Swap [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability		178
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset		0
Derivative Liability		$ 178

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, and obligation to return cash collateral under master netting arrangements.

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