GOODWILL (Goodwill Roll Forward) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($)
Goodwill [Roll Forward]
Balance as of January 1, 2022	$ 530,723
Goodwill impairment	(686)
Effect of net foreign currency exchange rate changes	(18,940)
Balance as of June 30, 2022	521,267
Emakina Group SA
Goodwill [Roll Forward]
Purchase accounting adjustments	423
PolSource S.A.
Goodwill [Roll Forward]
Purchase accounting adjustments	(74)
CORE SE
Goodwill [Roll Forward]
Purchase accounting adjustments	3
Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
Purchase accounting adjustments	(504)
2022 Acquisitions
Goodwill [Roll Forward]
2022 acquisitions	10,322
North America
Goodwill [Roll Forward]
Balance as of January 1, 2022	217,594
Goodwill impairment	0
Effect of net foreign currency exchange rate changes	(556)
Balance as of June 30, 2022	216,475
North America | Emakina Group SA
Goodwill [Roll Forward]
Purchase accounting adjustments	0
North America | PolSource S.A.
Goodwill [Roll Forward]
Purchase accounting adjustments	(44)
North America | CORE SE
Goodwill [Roll Forward]
Purchase accounting adjustments	0
North America | Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
Purchase accounting adjustments	(519)
North America | 2022 Acquisitions
Goodwill [Roll Forward]
2022 acquisitions	0
Europe
Goodwill [Roll Forward]
Balance as of January 1, 2022	312,413
Goodwill impairment	0
Effect of net foreign currency exchange rate changes	(18,354)
Balance as of June 30, 2022	304,792
Europe | Emakina Group SA
Goodwill [Roll Forward]
Purchase accounting adjustments	423
Europe | PolSource S.A.
Goodwill [Roll Forward]
Purchase accounting adjustments	(30)
Europe | CORE SE
Goodwill [Roll Forward]
Purchase accounting adjustments	3
Europe | Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
Purchase accounting adjustments	15
Europe | 2022 Acquisitions
Goodwill [Roll Forward]
2022 acquisitions	10,322
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 June 30, 2022	0
Russia | Emakina Group SA
Goodwill [Roll Forward]
Purchase accounting adjustments	0
Russia | PolSource S.A.
Goodwill [Roll Forward]
Purchase accounting adjustments	0
Russia | CORE SE
Goodwill [Roll Forward]
Purchase accounting adjustments	0
Russia | Other 2021 acquisitions purchase accounting adjustment
Goodwill [Roll Forward]
Purchase accounting adjustments	0
Russia | 2022 Acquisitions
Goodwill [Roll Forward]
2022 acquisitions	$ 0