GOODWILL AND OTHER INTANGIBLE ASSETS - Carrying Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	$ 599,609	$ 554,509
Total accumulated amortization	(262,596)	(253,499)
Total intangible assets, net	337,013	301,010
Referral sources
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	551,188	514,388
Total accumulated amortization	(238,602)	(230,371)
Trademarks/names
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	47,436	39,136
Total accumulated amortization	(23,416)	(22,599)
Other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	985	985
Total accumulated amortization	$ (578)	$ (529)