Note 11 - Related Party Transactions - Schedule of Related Party Transactions (Details) - US Subsidiary Of Elekta Member - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Equipment purchases and de-install costs	$ 1,844,000	$ 1,906,000
Costs incurred to maintain equipment	1,094,000	759,000
Total related party transactions	2,938,000	2,665,000
Accounts payable and other accrued liabilities	$ 497,000	$ 1,992,000