Note 1 - Business and Basis of Presentation (Details Textual)		19 Months Ended
Jun. 12, 2020 USD ($)	Dec. 31, 2021 USD ($)
OR21, LLC [Member]
Equity Method Investment, Ownership Percentage		50.00%
Gamma Knife Center Ecuador S.A. (GKCE) [Member]
Noncontrolling Interest, Ownership Percentage by Parent		99.30%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		0.70%
Gamma Knife Center Ecuador S.A. (GKCE) [Member]
Business Combination, Consideration Transferred, Total	$ 2,000,000	$ 2,883,000
Payments to Acquire Businesses, Gross	575,000
Business Combination, Consideration Transferred, Liabilities Incurred	$ 1,425,000
GK Financing, LLC (GKF) [Member] \| Gamma Knife Center Ecuador S.A. (GKCE) [Member]
Business Acquisition, Percentage of Voting Interests Acquired	98.00%
Third Party [Member] \| Gamma Knife Center Ecuador S.A. (GKCE) [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		0.70%
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		14

The number of medical centers.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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