Note 1 - Summary of Significant Accounting Policies - Accumulated Other Comprehensive Earnings (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Balance	$ 60,440,931	$ 74,703,914
Net current period other comprehensive earnings (loss)	1,596,353	(4,969,069)
Balance	63,598,529	69,690,229
AOCI Attributable to Parent [Member]
Balance	(8,841,517)	2,920,027
Other comprehensive earnings (loss) before reclassification	1,564,342	(4,961,385)
Amount reclassified from accumulated other comprehensive earnings (loss)	32,011	(7,684)
Net current period other comprehensive earnings (loss)	1,596,353	(4,969,069)
Balance	$ (7,245,164)	$ (2,049,042)