DERIVATIVES (Outstanding Derivative Balances) (Details) - Commodity Risk - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivatives And Hedging Activities [Line Items]
Gross Derivative Assets	$ (1)	$ 5
Derivative Asset, Netting	0	0
Cash Collateral	12	6
Total Derivative Balance, Assets	11	11
Current assets – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Assets	35	36
Derivative Asset, Netting	(6)	(6)
Cash Collateral	11	4
Total Derivative Balance, Assets	40	34
Other noncurrent assets – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Assets	133	130
Derivative Asset, Netting	0	(6)
Cash Collateral	0	0
Total Derivative Balance, Assets	133	124
Current liabilities – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Liabilities	(31)	(31)
Derivative Liability, Netting	6	6
Cash Collateral	1	2
Total Derivative Balance, Liabilities	(24)	(23)
Noncurrent liabilities – other
Derivatives And Hedging Activities [Line Items]
Gross Derivative Liabilities	(138)	(130)
Derivative Liability, Netting	0	6
Cash Collateral	0	0
Total Derivative Balance, Liabilities	$ (138)	$ (124)