EQUITY METHOD INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Equity Method Investments [Line Items]
Additional cash investments	$ 12,400	$ 92,100
Double E
Schedule Of Equity Method Investments [Line Items]
Result of operations	$ 0	$ 0
OGC \| Principal Owner
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership interest	38.20%	38.20%	38.50%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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