INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Variable Interest Entity [Line Items]
Minimum ownership percentage for controlling interest (percent)	50.00%			50.00%
Maximum ownership percentage for equity method investment (percent)	50.00%			50.00%
Equity method investment, aggregate cost	$ 45,500			$ 45,500		$ 40,500
Maximum ownership percentage for cost method investment (percent)	20.00%			20.00%
Purchase of cost method investment			$ 15,000	$ 0	$ 15,000
Investment Owned, at Cost	$ 20,000			20,000		20,000
Investment impairment	0	$ 3,009		0	$ 3,009
Cash and cash equivalents	78,112			78,112		40,540
Patient accounts receivable	319,580			319,580		296,785
Other current assets	33,097			33,097		26,415
Total current assets	467,227			467,227		388,961
Property and equipment	39,631			39,631		16,026
Operating lease right of use assets	87,834			87,834		102,856
Goodwill	1,244,679			1,244,679		1,287,399
Intangible assets	103,634			103,634		101,167
Other assets	84,412			84,412		79,836
Total assets	2,027,417			2,027,417		1,976,245
Accounts payable	34,555			34,555		43,735
Payroll and employee benefits	126,989			126,989		125,387
Accrued expenses	139,100			139,100		137,390
Operating lease liabilities	26,111			26,111		33,521
Total liabilities	933,899			933,899		869,672
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Cash and cash equivalents	8,600			8,600		15,600
Patient accounts receivable	7,000			7,000		6,100
Other current assets	100			100		600
Total current assets	15,700			15,700		22,300
Property and equipment	100			100		100
Operating lease right of use assets	100			100		100
Goodwill	8,500			8,500		8,500
Intangible assets	400			400		400
Other assets	100			100		200
Total assets	24,900			24,900		31,600
Accounts payable	400			400		100
Payroll and employee benefits	800			800		500
Accrued expenses	6,900			6,900		5,800
Operating lease liabilities	0			0		100
Current portion of long-term obligations	0			0		200
Total liabilities	$ 8,100			$ 8,100		$ 6,700