DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Notional Amount and Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Foreign currency exchange contracts \| Maximum
Derivative Instruments and Hedging Activities
Term of derivative instrument	1 month
Not designated as hedging instruments \| Accounts receivable, net \| Receive USD/pay GBP
Derivative Instruments and Hedging Activities
Notional amount, Assets	$ 43,540
Fair Value, Assets	176
Not designated as hedging instruments \| Accounts receivable, net \| Receive USD/pay COP
Derivative Instruments and Hedging Activities
Notional amount, Assets	3,445
Fair Value, Assets	5
Not designated as hedging instruments \| Accounts receivable, net \| Receive SGD/pay USD
Derivative Instruments and Hedging Activities
Notional amount, Assets		$ 8,341
Fair Value, Assets		30
Not designated as hedging instruments \| Accounts receivable, net \| Receive NOK/pay USD
Derivative Instruments and Hedging Activities
Notional amount, Assets		902
Fair Value, Assets		13
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay GBP
Derivative Instruments and Hedging Activities
Notional amount, Liabilities		40,648
Fair Value, Liabilities		(323)
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay COP
Derivative Instruments and Hedging Activities
Notional amount, Liabilities		2,931
Fair Value, Liabilities		(33)
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay ZAR
Derivative Instruments and Hedging Activities
Notional amount, Liabilities	12,030	8,618
Fair Value, Liabilities	(138)	(68)
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay AUD
Derivative Instruments and Hedging Activities
Notional amount, Liabilities	16,025	15,124
Fair Value, Liabilities	(99)	(105)
Not designated as hedging instruments \| Accrued liabilities \| Receive EUR/pay USD
Derivative Instruments and Hedging Activities
Notional amount, Liabilities	25,470
Fair Value, Liabilities	(61)
Not designated as hedging instruments \| Accrued liabilities \| Receive SGD/pay USD
Derivative Instruments and Hedging Activities
Notional amount, Liabilities	9,389
Fair Value, Liabilities	(12)
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay NZD
Derivative Instruments and Hedging Activities
Notional amount, Liabilities	2,106	2,952
Fair Value, Liabilities	$ (4)	(4)
Not designated as hedging instruments \| Accrued liabilities \| Receive USD/pay EUR
Derivative Instruments and Hedging Activities
Notional amount, Liabilities		6,894
Fair Value, Liabilities		$ (2)

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

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- Definition

Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

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Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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