DERIVATIVES AND HEDGING ACTIVITIES - Fair value of derivative contracts (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Currency forward contracts, asset	$ 1,056	$ 96
Currency forward contracts, liability	0	2,536
Derivatives designated as hedging instruments
Buy Contracts
Notional amounts	85,648	92,956
Derivatives not designated as hedging instruments
Buy Contracts
Notional amounts	0	57,844
Other current assets \| Derivatives designated as hedging instruments \| Currency forward and option contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Currency forward contracts, asset	1,056	27
Other current assets \| Derivatives not designated as hedging instruments \| Currency forward and option contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Currency forward contracts, asset	0	69
Other accrued liabilities \| Derivatives designated as hedging instruments \| Currency forward and option contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Currency forward contracts, liability	0	2,122
Other accrued liabilities \| Derivatives not designated as hedging instruments \| Currency forward and option contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Currency forward contracts, liability	$ 0	$ 414

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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