DERIVATIVES - Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Commodity Contracts
Fair Value of Derivatives
Total derivatives	$ 0	$ 0
Commodity Contracts \| Other current assets
Fair Value of Derivatives
Gross Amounts Offset in the Balance Sheet	(10)	(84)
Commodity Contracts \| Other assets
Fair Value of Derivatives
Gross Amounts Offset in the Balance Sheet	0	(9)
Commodity Contracts \| Accrued liabilities
Fair Value of Derivatives
Gross Amounts Offset in the Balance Sheet	10	84
Commodity Contracts \| Other long-term liabilities
Fair Value of Derivatives
Gross Amounts Offset in the Balance Sheet	0	9
Interest Rate Contracts \| Other assets
Fair Value of Derivatives
Interest rate derivative assets	0	4
Recognized Fair Value \| Commodity Contracts
Fair Value of Derivatives
Total derivatives	35	178
Recognized Fair Value \| Commodity Contracts \| Other current assets
Fair Value of Derivatives
Gross Amounts Recognized at Fair Value	49	252
Recognized Fair Value \| Commodity Contracts \| Other assets
Fair Value of Derivatives
Gross Amounts Recognized at Fair Value	1	23
Recognized Fair Value \| Commodity Contracts \| Accrued liabilities
Fair Value of Derivatives
Gross Amounts Recognized at Fair Value	(15)	(87)
Recognized Fair Value \| Commodity Contracts \| Other long-term liabilities
Fair Value of Derivatives
Gross Amounts Recognized at Fair Value	0	(10)
Presented in the Balance Sheet \| Commodity Contracts
Fair Value of Derivatives
Total derivatives	35	178
Presented in the Balance Sheet \| Commodity Contracts \| Other current assets
Fair Value of Derivatives
Net Fair Value Presented in the Balance Sheet	39	168
Presented in the Balance Sheet \| Commodity Contracts \| Other assets
Fair Value of Derivatives
Net Fair Value Presented in the Balance Sheet	1	14
Presented in the Balance Sheet \| Commodity Contracts \| Accrued liabilities
Fair Value of Derivatives
Net Fair Value Presented in the Balance Sheet	(5)	(3)
Presented in the Balance Sheet \| Commodity Contracts \| Other long-term liabilities
Fair Value of Derivatives
Net Fair Value Presented in the Balance Sheet	$ 0	$ (1)

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.

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Fair value, after the 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 not elected to be offset.

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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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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