DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Derivative Assets and Liabilities and Locations on Consolidated Balance Sheet (Details) - Recurring - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative asset	$ 10	$ 9
Derivative liability	247	103
Current Assets: Other current assets
Derivatives, Fair Value [Line Items]
Derivative asset	1	2
Other Assets: Deferred charges and other
Derivatives, Fair Value [Line Items]
Derivative asset	9	7
Current Liabilities: Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	14	0
Deferred Credits and Other Noncurrent Liabilities: Other
Derivatives, Fair Value [Line Items]
Derivative liability	$ 233	$ 103