GOODWILL (Goodwill Roll Forward) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2022	$ 530,723
Goodwill impairment	(686)
Effect of net foreign currency exchange rate changes	(4,460)
Balance as of March 31, 2022	534,136
Emakina Group SA
Goodwill [Roll Forward]
2022 acquisition	423
PolSource S.A.
Goodwill [Roll Forward]
2022 acquisition	(74)
CORE SE
Goodwill [Roll Forward]
2022 acquisition	120
Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
2022 acquisition	(377)
2022 Acquisitions
Goodwill [Roll Forward]
Acquisition	8,467
North America
Goodwill [Roll Forward]
Balance as of January 1, 2022	217,594
Goodwill impairment	0
Effect of net foreign currency exchange rate changes	(80)
Balance as of March 31, 2022	216,951
North America \| Emakina Group SA
Goodwill [Roll Forward]
2022 acquisition	0
North America \| PolSource S.A.
Goodwill [Roll Forward]
2022 acquisition	(44)
North America \| CORE SE
Goodwill [Roll Forward]
2022 acquisition	0
North America \| Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
2022 acquisition	(519)
North America \| 2022 Acquisitions
Goodwill [Roll Forward]
Acquisition	0
Europe
Goodwill [Roll Forward]
Balance as of January 1, 2022	312,413
Goodwill impairment	0
Effect of net foreign currency exchange rate changes	(4,350)
Balance as of March 31, 2022	317,185
Europe \| Emakina Group SA
Goodwill [Roll Forward]
2022 acquisition	423
Europe \| PolSource S.A.
Goodwill [Roll Forward]
2022 acquisition	(30)
Europe \| CORE SE
Goodwill [Roll Forward]
2022 acquisition	120
Europe \| Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
2022 acquisition	142
Europe \| 2022 Acquisitions
Goodwill [Roll Forward]
Acquisition	8,467
Russia
Goodwill [Roll Forward]
Balance as of January 1, 2022	716
Goodwill impairment	(686)
Effect of net foreign currency exchange rate changes	(30)
Balance as of March 31, 2022	0
Russia \| Emakina Group SA
Goodwill [Roll Forward]
2022 acquisition	0
Russia \| PolSource S.A.
Goodwill [Roll Forward]
2022 acquisition	0
Russia \| CORE SE
Goodwill [Roll Forward]
2022 acquisition	0
Russia \| Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
2022 acquisition	0
Russia \| 2022 Acquisitions
Goodwill [Roll Forward]
Acquisition	$ 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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