PROPERTY AND EQUIPMENT - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Equipment originally acquired under finance/capital lease	$ 13,235	$ 13,971
Total property and equipment cost	1,630,450	1,441,300
Accumulated depreciation	(935,659)	(836,899)
Property and equipment, net	694,791	604,401
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	250	250
Medical equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	807,624	714,400
Computer and office equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	134,355	127,540
Software costs
Property, Plant and Equipment [Line Items]
Property and equipment, gross	56,261	47,286
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 618,725	$ 537,853