BUSINESS COMBINATIONS AND RELATED ACTIVITY - Assets and Liabilities Assumed (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Aug. 01, 2023 USD ($)	Apr. 01, 2023 USD ($)	Feb. 01, 2023 USD ($)	Jan. 01, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 09, 2022 USD ($)	Dec. 01, 2022 USD ($)	Nov. 01, 2022 USD ($) loan	Oct. 01, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 679,463					$ 677,665						$ 513,820
C.C.D.G.L.R. & S Services Inc.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total					$ 3,500
Property and equipment					435
Right of Use Assets					1,689
Goodwill					3,015
Intangible Assets					50
Other					0
Right of Use Liabilities					(1,689)
Southern California Diagnostic Imaging, Inc.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total					1,815
Property and equipment					466
Right of Use Assets					1,184
Goodwill					1,272
Intangible Assets					50
Other					27
Right of Use Liabilities					$ (1,184)
Inglewood Imaging Center, LLC
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total				$ 2,600
Property and equipment				877
Right of Use Assets				1,188
Goodwill				1,658
Intangible Assets				50
Other				15
Right of Use Liabilities				(1,188)
Ramapo Radiology Associates, P.C.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total				2,000
Property and equipment				1,663
Right of Use Assets				3,775
Goodwill				229
Intangible Assets				100
Other				8
Right of Use Liabilities				$ (3,775)
Madison Radiology Medical Group, Inc.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total			$ 250
Property and equipment			100
Right of Use Assets			0
Goodwill			150
Intangible Assets			0
Other			0
Right of Use Liabilities			$ 0
Delaware Diagnostic Imaging, P.A.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total		$ 600
Property and equipment		401
Right of Use Assets		337
Goodwill		149
Intangible Assets		50
Other		0
Right of Use Liabilities		$ (337)
I F R C L L C Subsidiary One
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total											$ 8,200
Property and equipment											2,910
Right of Use Assets											1,703
Goodwill											5,271
Intangible Assets											0
Other											19
Right of Use Liabilities											(1,703)
I F R C L L C Subsidiary Two
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total											4,800
Property and equipment											2,103
Right of Use Assets											857
Goodwill											2,697
Intangible Assets											0
Other											0
Right of Use Liabilities											$ (857)
Montclair Radiological Associates, P.A.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total										$ 94,877
Property and equipment										16,414
Right of Use Assets										4,665
Goodwill										79,690
Intangible Assets										400
Other										(2,168)
Right of Use Liabilities										(4,124)
Contingent consideration to guarantee share value issued										$ 1,200
Heart & Lung Imaging Limited
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total									$ 32,000
Property and equipment									0
Right of Use Assets									0
Goodwill									16,200
Intangible Assets									15,800
Other									0
Right of Use Liabilities									0
Contingent consideration to guarantee share value issued	6,879					11,656			$ 10,800			$ 0
Chelsea Dignostic Radiology, P.C.
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total								$ 2,800
Property and equipment								568
Right of Use Assets								0
Goodwill								2,132
Intangible Assets								100
Other								0
Right of Use Liabilities								$ 0
North Jersey Imaging Center, LLC
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total							$ 104
Property and equipment							20
Right of Use Assets							0
Goodwill							55
Intangible Assets							25
Other							4
Right of Use Liabilities							$ 0
I F R C L L C
Business Acquisition [Line Items]
Number of subsidiaries acquired | loan									3
I F R C L L C | Joint Venture With Calvert Medical Imaging Centers LLC
Business Acquisition [Line Items]
Number of subsidiaries acquired | loan									1
Business Acquisitions
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	10,765					142,781
Property and equipment	3,942					22,015
Right of Use Assets	8,173					7,225
Goodwill	6,473					106,045
Intangible Assets	300					16,325
Other	50					(2,145)
Right of Use Liabilities	$ (8,173)					$ (6,684)