FINANCIAL INSTRUMENTS (Schedule of Fair Values of Derivative Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	$ 273	$ 270
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(121)	(130)
Derivative Asset	152	140
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	512	378
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(140)	(130)
Derivative Liability	372	248
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	21	1
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	141	142
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(55)	(64)
Derivative Asset	86	78
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	352	288
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(73)	(64)
Derivative Liability	279	224
Designated as Hedging Instrument [Member] \| Foreign Currency Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	51	90
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(46)	(47)
Derivative Asset	5	43
Designated as Hedging Instrument [Member] \| Foreign Currency Contract [Member] \| Accrued and Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	109	55
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(46)	(47)
Derivative Liability	63	8
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	4	2
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0	0
Derivative Liability	4	2
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Accrued and Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		3
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset		0
Derivative Liability		3
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	20	42
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(4)	(14)
Derivative Asset	16	28
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Deferred charges and other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	70	10
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(5)	(3)
Derivative Asset	65	7
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	143	196
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(12)	(3)
Derivative Liability	131	193
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Accrued and Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	96	32
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(15)	(14)
Derivative Liability	81	18
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	132	128
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(66)	(66)
Derivative Asset	66	62
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	160	90
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(67)	(66)
Derivative Liability	93	24
Not Designated as Hedging Instrument [Member] \| Foreign Currency Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	75	103
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(58)	(62)
Derivative Asset	17	41
Not Designated as Hedging Instrument [Member] \| Foreign Currency Contract [Member] \| Accrued and Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	107	84
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(58)	(62)
Derivative Liability	49	22
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	50	13
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(5)	(2)
Derivative Asset	45	11
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Deferred charges and other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	7	12
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	(3)	(2)
Derivative Asset	4	10
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	8	2
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(3)	(2)
Derivative Liability	5	0
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Accrued and Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	45	4
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(6)	(2)
Derivative Liability	$ 39	$ 2

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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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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