GOODWILL AND OTHER INTANGIBLE ASSETS - Carrying Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	$ 554,519	$ 549,066
Total accumulated amortization	(219,123)	(184,951)
Total intangible assets, net	335,396	364,115
Referral sources
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	514,388	509,646
Total accumulated amortization	(199,084)	(167,902)
Trademarks/names
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	39,136	38,508
Total accumulated amortization	(19,698)	(16,901)
Other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	995	912
Total accumulated amortization	$ (341)	$ (148)