FINANCIAL INSTRUMENTS (Schedule of Fair Values of Derivative Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Gross	$ 274	$ 336
Counterparty and Cash Collateral Netting	(106)	(125)
Net Amounts Included in the Consolidated Balance Sheets	168	211
Gross	530	425
Counterparty and Cash Collateral Netting	(111)	(140)
Net Amounts Included in the Consolidated Balance Sheets	419	285
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	5	26
Derivative Asset, Collateral, Obligation to Return Cash, Offset	3	34
Derivatives designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Gross	198	163
Counterparty and Cash Collateral Netting	(77)	(58)
Net Amounts Included in the Consolidated Balance Sheets	121	105
Gross	203	307
Counterparty and Cash Collateral Netting	(82)	(69)
Net Amounts Included in the Consolidated Balance Sheets	121	238
Derivatives designated as hedging instruments: \| Foreign currency \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	105	98
Counterparty and Cash Collateral Netting	(36)	(42)
Net Amounts Included in the Consolidated Balance Sheets	69	56
Derivatives designated as hedging instruments: \| Foreign currency \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Gross	46	46
Counterparty and Cash Collateral Netting	(36)	(42)
Net Amounts Included in the Consolidated Balance Sheets	10	4
Derivatives designated as hedging instruments: \| Commodities \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	44	47
Counterparty and Cash Collateral Netting	(25)	(13)
Net Amounts Included in the Consolidated Balance Sheets	19	34
Derivatives designated as hedging instruments: \| Commodities \| Deferred charges and other assets
Derivatives, Fair Value [Line Items]
Gross	28	18
Counterparty and Cash Collateral Netting	(3)	(3)
Net Amounts Included in the Consolidated Balance Sheets	25	15
Derivatives designated as hedging instruments: \| Commodities \| Other noncurrent obligations
Derivatives, Fair Value [Line Items]
Gross	38	86
Counterparty and Cash Collateral Netting	(4)	(9)
Net Amounts Included in the Consolidated Balance Sheets	34	77
Derivatives designated as hedging instruments: \| Commodities \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Gross	95	111
Counterparty and Cash Collateral Netting	(29)	(18)
Net Amounts Included in the Consolidated Balance Sheets	66	93
Derivatives designated as hedging instruments: \| Interest rates \| Other noncurrent obligations
Derivatives, Fair Value [Line Items]
Gross		64
Counterparty and Cash Collateral Netting		0
Net Amounts Included in the Consolidated Balance Sheets		64
Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Gross	76	173
Counterparty and Cash Collateral Netting	(29)	(67)
Net Amounts Included in the Consolidated Balance Sheets	47	106
Gross	327	118
Counterparty and Cash Collateral Netting	(29)	(71)
Net Amounts Included in the Consolidated Balance Sheets	298	47
Derivatives not designated as hedging instruments: \| Foreign currency \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	44	128
Counterparty and Cash Collateral Netting	(12)	(64)
Net Amounts Included in the Consolidated Balance Sheets	32	64
Derivatives not designated as hedging instruments: \| Foreign currency \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Gross	23	103
Counterparty and Cash Collateral Netting	(12)	(64)
Net Amounts Included in the Consolidated Balance Sheets	11	39
Derivatives not designated as hedging instruments: \| Commodities \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	18	41
Counterparty and Cash Collateral Netting	(3)	(1)
Net Amounts Included in the Consolidated Balance Sheets	15	40
Derivatives not designated as hedging instruments: \| Commodities \| Deferred charges and other assets
Derivatives, Fair Value [Line Items]
Gross	0	4
Counterparty and Cash Collateral Netting	0	(2)
Net Amounts Included in the Consolidated Balance Sheets	0	2
Derivatives not designated as hedging instruments: \| Commodities \| Other noncurrent obligations
Derivatives, Fair Value [Line Items]
Gross	1	8
Counterparty and Cash Collateral Netting	0	(3)
Net Amounts Included in the Consolidated Balance Sheets	1	5
Derivatives not designated as hedging instruments: \| Commodities \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Gross	17	7
Counterparty and Cash Collateral Netting	(3)	(4)
Net Amounts Included in the Consolidated Balance Sheets	14	$ 3
Fair Value, Inputs, Level 2 [Member] \| Derivatives designated as hedging instruments: \| Interest rates 6 \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	21
Counterparty and Cash Collateral Netting	(13)
Net Amounts Included in the Consolidated Balance Sheets	8
Fair Value, Inputs, Level 2 [Member] \| Derivatives designated as hedging instruments: \| Interest rates 6 \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	23
Counterparty and Cash Collateral Netting	(13)
Net Amounts Included in the Consolidated Balance Sheets	10
Fair Value, Inputs, Level 2 [Member] \| Derivatives designated as hedging instruments: \| Interest rates 6 \| Other Noncurrent Obligations
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	1
Counterparty and Cash Collateral Netting	0
Net Amounts Included in the Consolidated Balance Sheets	1
Fair Value, Inputs, Level 2 [Member] \| Derivatives not designated as hedging instruments: \| Interest rates 6 \| Other current assets
Derivatives, Fair Value [Line Items]
Gross	14
Counterparty and Cash Collateral Netting	(14)
Net Amounts Included in the Consolidated Balance Sheets	0
Fair Value, Inputs, Level 2 [Member] \| Derivatives not designated as hedging instruments: \| Interest rates 6 \| Deferred charges and other assets
Derivatives, Fair Value [Line Items]
Gross	0
Counterparty and Cash Collateral Netting	0
Net Amounts Included in the Consolidated Balance Sheets	0
Fair Value, Inputs, Level 2 [Member] \| Derivatives not designated as hedging instruments: \| Interest rates 6 \| Accrued and other current liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	136
Counterparty and Cash Collateral Netting	(14)
Net Amounts Included in the Consolidated Balance Sheets	122
Fair Value, Inputs, Level 2 [Member] \| Derivatives not designated as hedging instruments: \| Interest rates 6 \| Other Noncurrent Obligations
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	150
Counterparty and Cash Collateral Netting	0
Net Amounts Included in the Consolidated Balance Sheets	$ 150

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