SIGNIFICANT ACCOUNTING POLICIES - Narrative 1 (Details)	1 Months Ended	3 Months Ended		9 Months Ended
SIGNIFICANT ACCOUNTING POLICIES - Narrative 1 (Details)	Oct. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) incentivePlan	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) incentivePlan	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Jun. 07, 2023 shares
Schedule of Significant Accounting Policies [Line Items]
Number of plans \| incentivePlan		1		1
Number of shares authorized (in shares) \| shares							20,100,000
Contracts receivable, factoring receivable		$ 4,100,000		$ 4,100,000		$ 4,200,000
Deferred financing costs, net of accumulated amortization		1,800,000		1,800,000		2,300,000
Acquisition-related cost		2,100,000	$ 400,000	5,100,000	$ 400,000
Goodwill		827,532,000		827,532,000		$ 710,663,000
Loss on impairment	$ 0
Intangible asset amortization expense		4,500,000	3,100,000	10,800,000	9,400,000
Income tax expense (benefit)		$ 6,385,000	$ 4,335,000	$ 3,807,000	$ 4,927,000
Effective tax rate		31.50%	26.10%	34.60%	16.70%
Lease abandonment charges				$ 8,300,000
Management service contracts
Schedule of Significant Accounting Policies [Line Items]
Useful life		25 years		25 years
Leasehold Improvements
Schedule of Significant Accounting Policies [Line Items]
Impairment loss				$ 6,500,000
Impairment of long lived asset				$ 1,900,000
Minimum \| Restated Plan
Schedule of Significant Accounting Policies [Line Items]
Share-based payment award, award vesting period				3 years
Share-based payment award, expiration period				5 years
Minimum \| Amounts Returned to Property and Equipment
Schedule of Significant Accounting Policies [Line Items]
PPE estimated useful lives		3 years		3 years
Minimum \| Leasehold Improvements
Schedule of Significant Accounting Policies [Line Items]
PPE estimated useful lives		3 years		3 years
Maximum \| Restated Plan
Schedule of Significant Accounting Policies [Line Items]
Share-based payment award, award vesting period				5 years
Share-based payment award, expiration period				10 years
Maximum \| Amounts Returned to Property and Equipment
Schedule of Significant Accounting Policies [Line Items]
PPE estimated useful lives		15 years		15 years
Maximum \| Leasehold Improvements
Schedule of Significant Accounting Policies [Line Items]
PPE estimated useful lives		15 years		15 years

RadNet, Inc. 10-Q