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GOODWILL AND LONG-LIVED ASSETS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment	$ 0	$ 0	$ 0	$ 109,486
Long-lived asset impairment	0	0	0	22,351
Intangible asset amortization expense	$ 2,300	2,400	$ 4,560	4,923
International
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment				109,500
Long-lived asset impairment		400		$ 22,400
North America
Finite-Lived Intangible Assets [Line Items]
Long-lived asset impairment		$ 13,500
Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life			1 year
Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life			10 years