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FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 30, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration					$ 2,500
Impairment loss	$ 0	$ 0	$ (109,486)	$ 0
Non-cash impairment charges related to long-lived assets	13,903		36,254
Restructuring Costs	13,903		13,903
Other than temporary impairments on equity method investments	$ 6,700
International
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment loss			$ (109,486)