INCOME TAXES - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Beginning Balance	$ 87,637	$ 87,359	$ 80,081
Increases related to prior year tax positions	3,754	1,500	960
Decreases related to prior year tax positions	(28,767)	(21)	(1,196)
Increases related to current year tax positions	6,086	7,533	9,571
Decreases based on settlements with taxing authorities	0	0	0
Decreases due to lapse of statute limitations	(3,875)	(9,447)	(3,777)
Foreign currency translation	(474)
Foreign currency translation		713	1,720
Ending Balance	$ 64,361	$ 87,637	$ 87,359

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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 decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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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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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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