Schedule of Fair Value of Derivative Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	$ 24	$ 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	386	338
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(288)	(165)
Derivative Asset	98	173
Derivative Liability, Fair Value, Gross Liability	602	521
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(300)	(171)
Derivative Liability	302	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	362	219
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(273)	(139)
Derivative Asset	89	80
Derivative Liability, Fair Value, Gross Liability	341	299
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(281)	(143)
Derivative Liability	60	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	24	119
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(15)	(26)
Derivative Asset	9	93
Derivative Liability, Fair Value, Gross Liability	261	222
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(19)	(28)
Derivative Liability	242	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	22	3
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(22)	(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	54	39
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(36)	(19)
Derivative Asset	18	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	17	74
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(12)	(25)
Derivative Asset	5	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	218	146
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(172)	(109)
Derivative Asset	46	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	7	4
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(3)	(1)
Derivative Asset	4	3
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	68	31
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(43)	(8)
Derivative Asset	25	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	44	93
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(36)	(19)
Derivative Liability	8	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	98	35
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(12)	(25)
Derivative Liability	86	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	214	151
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(178)	(112)
Derivative Liability	36	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	22	9
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(7)	(3)
Derivative Liability	15	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	22
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(22)
Derivative Liability	0
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	141
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0
Derivative Liability	141
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	(45)	(9)
Derivative Liability	$ 16	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 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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