Note 1 - Basis of Presentation (Details Textual)	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jul. 01, 2023 USD ($)	Jan. 01, 2023 USD ($)	Jul. 01, 2022 USD ($)	Apr. 27, 2022	Jan. 01, 2022 USD ($)
Number of Medical Centers	11		11
Number of Reportable Segments			2
GKCE [Member]
Accounts Receivable, after Allowance for Credit Loss	$ 1,416,000	$ 1,248,000	$ 1,416,000	$ 1,248,000	$ 980,000	$ 1,119,000	$ 1,145,000		$ 668,000
Rental Income from Medical Services [Member]
Revenue from Contract with Customer, Including Assessed Tax	3,946,000	4,101,000	12,987,000	12,382,000
PBRT Services [Member]
Revenue from Contract with Customer, Including Assessed Tax	2,219,000	2,358,000	7,078,000	6,705,000
Patient Income [Member]
Revenue from Contract with Customer, Including Assessed Tax	988,000	$ 727,000	2,440,000	$ 2,327,000
Equipment Sales [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 200,000		$ 200,000
Gamma Knife and PBRT Equipment [Member]
Number of Medical Centers	12		12
Lima, Peru and Guayaquil, Ecuador [Member]
Number of Single-unit Facilities	2		2
Newco [Member]
Equity Method Investment, Ownership Percentage								85.00%
Newco [Member] | Guadalupe [Member]
Equity Method Investment, Ownership Percentage								15.00%
OR21, LLC [Member]
Equity Method Investment, Ownership Percentage	50.00%		50.00%
OR21, LLC [Member] | Architectural Design Company [Member]
Equity Method Investment, Ownership Percentage	50.00%		50.00%