Note 1 - Summary of Significant Accounting Policies - Other Comprehensive Earnings (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Unrealized holding losses arising during the period, pre tax	$ (630,383)	$ (978,883)	$ (1,439,484)	$ 1,001,297
Unrealized holding losses arising during the period, tax	132,380	205,566	302,292	(210,272)
Unrealized holding losses arising during the period, after tax	(498,003)	(773,317)	(1,137,192)	791,025
Reclassification adjustment for losses included in net earnings, pre tax	22,747	11,378	21,580	51,897
Reclassification adjustment for losses included in net earnings, tax	(4,776)	(2,390)	(4,532)	(10,898)
Reclassification adjustment for losses included in net earnings, after tax	17,971	8,988	17,048	40,999
Total other comprehensive loss, pre tax	(607,636)	(967,505)	(1,417,904)	1,053,194
Total other comprehensive loss, tax	127,604	203,176	297,760	(221,170)
Total other comprehensive loss, after tax	$ (480,032)	$ (764,329)	$ (1,120,144)	$ 832,024