SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill, Long-lived assets, Leases, Uninsured risks (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Goodwill	$ 710,663,000	$ 679,463,000	$ 677,665,000
Indefinite lived intangible assets	13,000,000.0	9,000,000.0
Loss on impairment	1,275,000	3,949,000	$ 0
Lease abandonment charges	2,500,000	5,100,000
Workers' compensation liability, current	5,600,000	3,400,000
Medical malpractice deductible per incidence	10,000
Blue Shield | Minimum
Property, Plant and Equipment [Line Items]
Stop loss policy claim amount	250,000
Blue Shield | Maximum
Property, Plant and Equipment [Line Items]
Stop loss policy claim amount	1,000,000.0
Reinsurance Policy, Type [Axis]: Health Insurance Member
Property, Plant and Equipment [Line Items]
Self-insurance accrual	7,800,000	7,200,000
Leasehold improvements
Property, Plant and Equipment [Line Items]
Impairment of long lived asset	700,000	2,500,000
Impairment loss	1,800,000	$ 2,700,000
Aidence
Property, Plant and Equipment [Line Items]
Loss on impairment	$ 3,900,000