GOODWILL AND INTANGIBLE ASSETS, NET - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Balance, beginning of period	$ 0	$ 0
Foreign currency translation adjustments, net	(1,638)	0
Balance, end of period	297,525	0
Heavy 16
Goodwill [Roll Forward]
Acquisitions	18,204	0
H&G Entities
Goodwill [Roll Forward]
Acquisitions	55,876	0
Aurora
Goodwill [Roll Forward]
Acquisitions	149,505	0
Greenstar
Goodwill [Roll Forward]
Acquisitions	$ 75,578	$ 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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