EQUITY INVESTMENTS - Income From Equity Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Representation of investee financial information in the summarized equity method investments (as a percent)			100.00%
INCOME STATEMENT DATA:
Revenue	$ 28,549	$ 145,137	$ 76,305	$ 435,827
Operating income	16,177	42,637	42,650	132,446
Net income	12,374	24,262	32,817	75,394
Net income attributable to investee	$ 12,374	$ 22,748	$ 32,817	$ 70,877

Equity Method Investment, Summarized Financial Information, Net Income (Loss) Attributable To Equity Method Investee

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Represents the percentage of investee financial information in the summarized equity method investments.

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Amount of income (loss) from continuing operations reported by an equity method investee.

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The amount of net income (loss) reported by an equity method investment of the entity.

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Amount of revenue from sale of product and rendering of service reported by equity method investee.

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