GOODWILL - Schedule of Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Goodwill [Line Items]
Beginning balance	$ 1,098,659	$ 0
Business acquisitions	63,485	169,024
Measurement period adjustment	(2,133)	2,977
Ending balance	1,160,011	1,098,659
T P G Acquisition
Goodwill [Line Items]
Business acquisitions		926,658
Measurement period adjustment		$ 2,977
Ending balance	$ 926,658

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 increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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