RESTRUCTURING COSTS - Schedule of Restructuring liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	30 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020
Restructuring Reserve [Roll Forward]
Beginning balance			$ 2,172
Cost incurred and charged to expense	$ 5,790	$ 1,795	6,446	$ 3,468	$ 15,723
Cost paid or otherwise settled			(2,751)
Effect of change in exchange rates			(1)
Ending balance	$ 5,866		$ 5,866		$ 5,866

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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