Note 7 - Investments, Held to Maturity ("HTM") - Summary of HTM Securities in Unrealized Loss Position (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Fair value, less than 12 months, HTM	$ 119,802,046	$ 130,591,167
Unrealized losses, les then 12 months, HTM	3,125,875	3,947,948
Fair value, more than 12 months, HTM	28,177,551	9,334,438
Unrealized loss, more than 12 months, HTM	3,582,068	2,306,013
Fair value, unrealized loss position, HTM	147,979,597	139,925,605
Unrealized loss, unrealized loss position, HTM	6,707,943	6,253,961
US Treasury and Government [Member]
Fair value, less than 12 months, HTM	33,982,656	33,829,651
Unrealized losses, les then 12 months, HTM	709,002	682,198
Fair value, more than 12 months, HTM	0	0
Unrealized loss, more than 12 months, HTM	0	0
Fair value, unrealized loss position, HTM	33,982,656	33,829,651
Unrealized loss, unrealized loss position, HTM	709,002	682,198
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Fair value, less than 12 months, HTM	988,552	998,640
Unrealized losses, les then 12 months, HTM	11,448	1,360
Fair value, more than 12 months, HTM	0	0
Unrealized loss, more than 12 months, HTM	0	0
Fair value, unrealized loss position, HTM	988,552	998,640
Unrealized loss, unrealized loss position, HTM	11,448	1,360
Collateralized Loan Obligations [Member]
Fair value, less than 12 months, HTM	9,128,369	6,520,050
Unrealized losses, les then 12 months, HTM	81,883	59,090
Fair value, more than 12 months, HTM	0	0
Unrealized loss, more than 12 months, HTM	0	0
Fair value, unrealized loss position, HTM	9,128,369	6,520,050
Unrealized loss, unrealized loss position, HTM	81,883	59,090
Taxable Municipal Bonds [Member]
Fair value, less than 12 months, HTM	901,760	891,730
Unrealized losses, les then 12 months, HTM	55,302	60,134
Fair value, more than 12 months, HTM	0	0
Unrealized loss, more than 12 months, HTM	0	0
Fair value, unrealized loss position, HTM	901,760	891,730
Unrealized loss, unrealized loss position, HTM	55,302	60,134
Collateralized Mortgage-Backed Securities [Member]
Fair value, less than 12 months, HTM	74,800,709	88,351,096
Unrealized losses, les then 12 months, HTM	2,268,240	3,145,166
Fair value, more than 12 months, HTM	28,177,551	9,334,438
Unrealized loss, more than 12 months, HTM	3,582,068	2,306,013
Fair value, unrealized loss position, HTM	102,978,260	97,685,534
Unrealized loss, unrealized loss position, HTM	$ 5,850,308	$ 5,451,179