INTANGIBLE ASSETS AND GOODWILL - Carrying Value of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 274,728	$ 270,505
Accumulated Amortization	(50,174)	(31,663)
Net Carrying Amount	224,554	238,842
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	27,300	27,300
Accumulated Amortization	(3,031)	(1,940)
Net Carrying Amount	24,269	25,360
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	189,000	189,000
Accumulated Amortization	(35,795)	(22,909)
Net Carrying Amount	153,205	166,091
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	47,800	47,800
Accumulated Amortization	(9,958)	(6,373)
Net Carrying Amount	37,842	41,427
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,628	6,405
Accumulated Amortization	(1,390)	(441)
Net Carrying Amount	$ 9,238	$ 5,964