DERIVATIVES - Derivative Positions (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives measured at fair value
Total derivative liabilities, net	$ (250)	$ (4,306)
Commodity \| Commodity contracts - current
Derivatives measured at fair value
Derivative Assets	7,482	2,884
Commodity \| Commodity contracts - noncurrent
Derivatives measured at fair value
Derivative Assets	0	121
Commodity \| Commodity contracts - current
Derivatives measured at fair value
Derivative Liabilities	(6,402)	(6,390)
Commodity \| Commodity contracts - long-term
Derivatives measured at fair value
Derivative Liabilities	$ (1,330)	$ (921)

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 of the assets less the liabilities of a derivative or group of derivatives.

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