Note 8 - Loans Receivable, Net - Schedule of Loans (Details) - USD ($)	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Loans	$ 609,783,265		$ 560,987,903
Held for investment, allowance for credit loss	12,348,125	$ 12,283,325	11,177,753	$ 11,298,845	$ 11,197,954	$ 11,087,164
Deferred Loan Fees	459,424		806,238
Financing Receivable, Allowance for Credit Loss and Deferred Loan Fees	12,807,549		11,983,991
Total Loans Receivable, Net	596,975,716		549,003,912
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans	101,493,816		112,793,694
Held for investment, allowance for credit loss	2,149,483	2,200,850	2,323,397	2,219,458	2,104,386	2,401,196
Commercial Real Estate Portfolio Segment [Member] \| Residential Mortgage [Member]
Loans	159,980,843		110,056,973
Held for investment, allowance for credit loss	3,528,292	3,260,891	2,124,835	1,862,871	1,870,696	1,663,423
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member]
Loans	256,175,825		252,154,475
Held for investment, allowance for credit loss	4,314,652	4,427,006	4,804,282	4,858,457	4,736,314	4,832,440
Commercial and Agricultural Loans [Member]
Loans	34,404,989		30,647,975
Held for investment, allowance for credit loss	1,033,292	1,102,070	874,092	1,287,580	1,403,818	1,241,828
Consumer Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Loans	33,318,762		31,736,676
Held for investment, allowance for credit loss	666,328	654,278	598,807	607,356	606,847	517,512
Consumer Portfolio Segment [Member] \| Other Consumer Loans [Member]
Loans	24,409,030		23,598,110
Held for investment, allowance for credit loss	$ 656,078	$ 638,230	$ 452,340	$ 463,123	$ 475,893	$ 430,765

Amount of allowance for credit loss and deferred loan fees for financing receivables.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amortized cost, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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