GOODWILL (Goodwill Roll Forward) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2019	$ 166,832
Effect of net foreign currency exchange rate changes	499
Balance as of June 30, 2019	179,214
test IO
Goodwill [Roll Forward]
Acquisition	11,883
North America
Goodwill [Roll Forward]
Balance as of January 1, 2019	103,542
Effect of net foreign currency exchange rate changes	162
Balance as of June 30, 2019	106,881
North America \| test IO
Goodwill [Roll Forward]
Acquisition	3,177
Europe
Goodwill [Roll Forward]
Balance as of January 1, 2019	63,290
Effect of net foreign currency exchange rate changes	337
Balance as of June 30, 2019	72,333
Europe \| test IO
Goodwill [Roll Forward]
Acquisition	$ 8,706

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

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

+ References

No definition available.

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