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GOODWILL AND INTANGIBLE ASSETS, NET - Goodwill (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Goodwill [Roll Forward]
Balance at December 31, 2021			$ 204,868,000
Impairment charges	$ 189,572,000	$ 0	192,328,000	$ 0
Balance at June 30, 2022	$ 0		0
IGE Entities
Goodwill [Roll Forward]
Remeasurement adjustments and foreign currency translation adjustments, net			(21,304,000)
Greenstar
Goodwill [Roll Forward]
Remeasurement adjustments and foreign currency translation adjustments, net			7,000,000
All others
Goodwill [Roll Forward]
Remeasurement adjustments and foreign currency translation adjustments, net			$ (992,000)