GOODWILL AND INTANGIBLE ASSETS - Carrying Value of Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Finite-lived intangible assets, net
Finite-lived intangible assets	$ 980,953	$ 882,817
Foreign currency translation	987	1,792
Total finite-lived intangible assets	981,940	884,609
Less: accumulated amortization	(145,349)	(115,791)
Finite-lived intangible assets, net	836,591	768,818
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	654,000	654,000
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible assets, net	1,490,591	1,422,818
Management contracts
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	567,800	567,800
Trade name
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	$ 86,200	86,200
Management contracts
Finite-lived intangible assets, net
Weighted average amortization period	6 years
Finite-lived intangible assets	$ 707,073	641,737
Client relationships
Finite-lived intangible assets, net
Weighted average amortization period	10 years 4 months 24 days
Finite-lived intangible assets	$ 262,301	229,501
Trade name
Finite-lived intangible assets, net
Weighted average amortization period	8 years 2 months 12 days
Finite-lived intangible assets	$ 11,079	11,079
Other
Finite-lived intangible assets, net
Weighted average amortization period	2 years 7 months 6 days
Finite-lived intangible assets	$ 500	$ 500