Note 1 - Basis of Presentation (Details Textual)	3 Months Ended
	Mar. 31, 2022
Increase (Decrease) in Procedure Volumes, Percentage	2.00%
Number of Reportable Segments	2
OR21, LLC [Member]
Equity Method Investment, Ownership Percentage	50.00%
Architectural Design Company [Member] | OR21, LLC [Member]
Equity Method Investment, Ownership Percentage	50.00%
Gamma Knife Center Ecuador S.A. (GKCE) [Member] | Gamma Knife Units [Member]
Number of Medical Centers	12
Gamma Knife and PBRT Equipment [Member]
Number of Medical Centers	13
Lima, Peru and Guayaquil, Ecuador [Member]
Number of Single-unit Facilities	2