INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Variable Interest Entity [Line Items]
Minimum ownership percentage for controlling interest (percent)	50.00%
Maximum ownership percentage for equity method investment (percent)	50.00%
Equity method investment, aggregate cost	$ 38,900		$ 40,500
Maximum ownership percentage for cost method investment (percent)	20.00%
Purchase of cost method investment	$ 0	$ 15,000
Investment Owned, at Cost	20,000		20,000
Cash and cash equivalents	49,436		40,540
Patient accounts receivable	294,122		296,785
Other current assets	23,581		26,415
Total current assets	405,557		388,961
Property and equipment	33,353		16,026
Operating lease right of use assets	85,211		102,856
Goodwill	1,244,679		1,287,399
Intangible assets	99,929		101,167
Other assets	78,230		79,836
Total assets	1,946,959		1,976,245
Accounts payable	40,017		43,735
Payroll and employee benefits	122,723		125,387
Accrued expenses	137,899		137,390
Operating lease liabilities	25,453		33,521
Total liabilities	813,611		869,672
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Cash and cash equivalents	7,300		15,600
Patient accounts receivable	6,900		6,100
Other current assets	500		600
Total current assets	14,700		22,300
Property and equipment	100		100
Operating lease right of use assets	100		100
Goodwill	8,500		8,500
Intangible assets	400		400
Other assets	200		200
Total assets	24,000		31,600
Accounts payable	300		100
Payroll and employee benefits	600		500
Accrued expenses	6,400		5,800
Operating lease liabilities	0		100
Current portion of long-term obligations	200		200
Total liabilities	$ 7,500		$ 6,700