DERIVATIVES AND HEDGING ACTIVITIES (Fair Value of Derivative Contracts and Notional Amounts) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Derivatives designated as hedging instruments
Notional Disclosures [Abstract]
Currency forward and option contracts	$ 56,197	$ 92,956
Derivatives not designated as hedging instruments
Notional Disclosures [Abstract]
Currency forward and option contracts	0	57,844
Currency forward and option contracts \| Other current assets
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, assets	706	96
Currency forward and option contracts \| Other current assets \| Derivatives designated as hedging instruments
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, assets	706	27
Currency forward and option contracts \| Other current assets \| Derivatives not designated as hedging instruments
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, assets	0	69
Currency forward and option contracts \| Accrued liabilities
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, liabilities	22	2,536
Currency forward and option contracts \| Accrued liabilities \| Derivatives designated as hedging instruments
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, liabilities	22	2,122
Currency forward and option contracts \| Accrued liabilities \| Derivatives not designated as hedging instruments
Derivative, Fair Value, Net [Abstract]
Currency forward contracts, liabilities	$ 0	$ 414

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value of 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, not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

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