INCOME TAXES - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 64,361	$ 87,637	$ 87,359
Increases related to prior year tax positions	8,389	3,754	1,500
Decreases related to prior year tax positions	(22,541)	(28,767)	(21)
Increases related to current year tax positions	1,994	6,086	7,533
Decreases based on settlements with taxing authorities	0	0	0
Decreases due to lapse of statute limitations	(5,640)	(3,875)	(9,447)
Foreign currency translation	2,397		713
Foreign currency translation		(474)
Ending Balance	$ 48,960	$ 64,361	$ 87,637

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

No definition available.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from foreign currency translation.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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