Note 3 - Investments (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2021	Dec. 31, 2022
Equity Method Investments	$ 3,885,000
Gain (Loss) on Investments, Total	295,000	$ 103,000
Gain (Loss) on Investments, Total	(295,000)	$ (103,000)
Long-Term Investments, Total	4,885,000			$ 5,180,000
Privately Held Company Providing Supply Chain and Receivables Financing [Member]
Payments to Acquire Investments, Total			$ 1,000,000
Long-Term Investments, Total	$ 1,000,000