GOODWILL (Goodwill Roll Forward) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2019	$ 166,832
Effect of net foreign currency exchange rate changes	(1,865)
Balance as of September 30, 2019	186,299
test IO
Goodwill [Roll Forward]
Acquisition	12,085
Other 2019 Acquisitions
Goodwill [Roll Forward]
Acquisition	9,505
Think
Goodwill [Roll Forward]
Purchase accounting adjustments	(258)
North America
Goodwill [Roll Forward]
Balance as of January 1, 2019	103,542
Effect of net foreign currency exchange rate changes	(145)
Balance as of September 30, 2019	113,417
North America \| test IO
Goodwill [Roll Forward]
Acquisition	3,310
North America \| Other 2019 Acquisitions
Goodwill [Roll Forward]
Acquisition	6,710
North America \| Think
Goodwill [Roll Forward]
Purchase accounting adjustments	0
Europe
Goodwill [Roll Forward]
Balance as of January 1, 2019	63,290
Effect of net foreign currency exchange rate changes	(1,714)
Balance as of September 30, 2019	72,121
Europe \| test IO
Goodwill [Roll Forward]
Acquisition	8,775
Europe \| Other 2019 Acquisitions
Goodwill [Roll Forward]
Acquisition	2,028
Europe \| Think
Goodwill [Roll Forward]
Purchase accounting adjustments	(258)
Russia
Goodwill [Roll Forward]
Balance as of January 1, 2019	0
Effect of net foreign currency exchange rate changes	(6)
Balance as of September 30, 2019	761
Russia \| test IO
Goodwill [Roll Forward]
Acquisition	0
Russia \| Other 2019 Acquisitions
Goodwill [Roll Forward]
Acquisition	767
Russia \| Think
Goodwill [Roll Forward]
Purchase accounting adjustments	$ 0

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.

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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.

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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.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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