GOODWILL AND OTHER INTANGIBLE ASSETS - Carrying Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	$ 554,509		$ 554,509		$ 554,519
Total accumulated amortization	(236,307)		(236,307)		(219,123)
Total intangible assets, net	318,202		318,202		335,396
Amortization expense for intangible assets	8,600	$ 8,500	17,200	$ 17,000
Referral sources
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	514,388		514,388		514,388
Total accumulated amortization	(214,728)		(214,728)		(199,084)
Trademarks/names
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	39,136		39,136		39,136
Total accumulated amortization	(21,149)		(21,149)		(19,698)
Other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Total gross intangible assets	985		985		995
Total accumulated amortization	$ (430)		$ (430)		$ (341)