DERIVATIVES - Summary of Company's derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative assets - current	$ 12,860	$ 427
Derivative liabilities - current	(8,630)	(5,044)
Total derivative liabilities, net	(21,770)	(7,483)
Fair Value, Recurring
Derivative [Line Items]
Derivative assets - current	12,860	427
Derivative assets - non-current	4,469	187
Derivative liabilities - current	(8,630)	(5,044)
Derivative liabilities - non-current	(13,140)	(2,439)
Total derivative liabilities, net	(4,441)	(6,869)
ARM Sales Agreement \| Embedded Derivative Financial Instruments
Derivative [Line Items]
Total derivative liabilities, net	(20,600)
ARM Sales Agreement \| Fair Value, Recurring \| Embedded Derivative Financial Instruments
Derivative [Line Items]
Derivative liabilities - current	(7,500)	(800)
Derivative liabilities - non-current	$ (13,100)	$ (2,400)

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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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