LONG TERM DEBT - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) note	Dec. 31, 2019 USD ($) note
Debt Instrument [Line Items]
Number of notes \| note	7	6
Debt issuance costs	$ 27
Gamma Knife Unit
Debt Instrument [Line Items]
Aggregate net book value	11,023	$ 13,130
Accounts receivable	$ 1,718	$ 1,848
Minimum
Debt Instrument [Line Items]
Monthly installments	36 years
Long-term debt percentage rate	3.67%
Maximum
Debt Instrument [Line Items]
Monthly installments	84 months
Long-term debt percentage rate	6.90%

Long Term Debt, Monthly Installments

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- Definition

Number Of Debt Instruments

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- Definition

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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