Note 8 - Loans Receivable, Net - Allowance for Credit Loss (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jan. 01, 2023	Dec. 31, 2022
Balance	$ 12,283,325	$ 11,197,954	$ 11,177,753	$ 11,087,164
(Reversal of) Provision for Credit Losses	50,000		376,000
Charge-Offs	(53,513)	(54,192)	(143,071)	(97,884)
Recoveries	68,313	155,083	153,249	309,565
Balance	12,348,125	11,298,845	12,348,125	11,298,845
Provision for Credit Losses	0	0	221,000	0
Individually evaluated for impairment						$ 0
Collectively evaluated for impairment						11,177,753
Held for investment, allowance for credit loss	12,348,125	11,298,845	12,348,125	11,298,845		11,177,753
Individually evaluated for impairment						5,565,878
Collectively evaluated for impairment						555,422,025
Loans	609,783,265		609,783,265			560,987,903
Ending Balance	173,100,000		173,100,000
Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			784,194
Held for investment, allowance for credit loss						784,194
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Held for investment, allowance for credit loss					$ 784,000
Unfunded Loan Commitment [Member]
Beginning Balance	1,108,614		0
Reversal of provision for unfunded commitments	(50,000)		(155,000)
Ending Balance	1,058,614		1,058,614
Unfunded Loan Commitment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance			1,213,614
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Balance	2,200,850	2,104,386	2,323,397	2,401,196
(Reversal of) Provision for Credit Losses	(55,278)		(449,432)
Charge-Offs	0	0	(1,270)	0
Recoveries	3,911	15,460	13,051	31,023
Balance	2,149,483	2,219,458	2,149,483	2,219,458
Provision for Credit Losses		99,612		(212,761)
Individually evaluated for impairment						0
Collectively evaluated for impairment						2,323,397
Held for investment, allowance for credit loss	2,149,483	2,219,458	2,149,483	2,219,458		2,323,397
Individually evaluated for impairment						114,630
Collectively evaluated for impairment						112,679,064
Loans	101,493,816		101,493,816			112,793,694
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			263,737
Held for investment, allowance for credit loss						263,737
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member]
Balance	3,260,891	1,870,696	2,124,835	1,663,423
(Reversal of) Provision for Credit Losses	236,084		896,261
Charge-Offs	0	0	0	0
Recoveries	31,317	9,678	45,317	37,609
Balance	3,528,292	1,862,871	3,528,292	1,862,871
Provision for Credit Losses		(17,503)		161,839
Individually evaluated for impairment						0
Collectively evaluated for impairment						2,124,835
Held for investment, allowance for credit loss	3,528,292	1,862,871	3,528,292	1,862,871		2,124,835
Individually evaluated for impairment						1,089,308
Collectively evaluated for impairment						108,967,665
Loans	159,980,843		159,980,843			110,056,973
Commercial Real Estate Portfolio Segment [Member] | Residential Mortgage [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			461,879
Held for investment, allowance for credit loss						461,879
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member]
Balance	4,427,006	4,736,314	4,804,282	4,832,440
(Reversal of) Provision for Credit Losses	(117,370)		(164,187)
Charge-Offs	0	0	0	0
Recoveries	5,016	77,479	15,049	126,958
Balance	4,314,652	4,858,457	4,314,652	4,858,457
Provision for Credit Losses		44,664		(100,941)
Individually evaluated for impairment						0
Collectively evaluated for impairment						4,804,282
Held for investment, allowance for credit loss	4,314,652	4,858,457	4,314,652	4,858,457		4,804,282
Individually evaluated for impairment						4,281,702
Collectively evaluated for impairment						247,872,773
Loans	256,175,825		256,175,825			252,154,475
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			(340,492)
Held for investment, allowance for credit loss						(340,492)
Commercial and Agricultural Loans [Member]
Balance	1,102,070	1,403,818	874,092	1,241,828
(Reversal of) Provision for Credit Losses	(75,644)		44,001
Charge-Offs	0	0	(15,880)	0
Recoveries	6,866	1,281	18,627	26,109
Balance	1,033,292	1,287,580	1,033,292	1,287,580
Provision for Credit Losses		(117,519)		19,643
Individually evaluated for impairment						0
Collectively evaluated for impairment						874,092
Held for investment, allowance for credit loss	1,033,292	1,287,580	1,033,292	1,287,580		874,092
Individually evaluated for impairment						31,446
Collectively evaluated for impairment						30,616,529
Loans	34,404,989		34,404,989			30,647,975
Commercial and Agricultural Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			112,452
Held for investment, allowance for credit loss						112,452
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member]
Balance	654,278	606,847	598,807	517,512
(Reversal of) Provision for Credit Losses	690		(76,130)
Charge-Offs	0	0	(1,488)	0
Recoveries	11,360	38,190	37,591	45,776
Balance	666,328	607,356	666,328	607,356
Provision for Credit Losses		(37,681)		44,068
Individually evaluated for impairment						0
Collectively evaluated for impairment						598,807
Held for investment, allowance for credit loss	666,328	607,356	666,328	607,356		598,807
Individually evaluated for impairment						48,792
Collectively evaluated for impairment						31,687,884
Loans	33,318,762		33,318,762			31,736,676
Consumer Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			107,548
Held for investment, allowance for credit loss						107,548
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member]
Balance	638,230	475,893	452,340	430,765
(Reversal of) Provision for Credit Losses	61,518		125,487
Charge-Offs	(53,513)	(54,192)	(124,433)	(97,884)
Recoveries	9,843	12,995	23,614	42,090
Balance	656,078	463,123	656,078	463,123
Provision for Credit Losses		28,427		88,152
Individually evaluated for impairment						0
Collectively evaluated for impairment						452,340
Held for investment, allowance for credit loss	656,078	$ 463,123	656,078	$ 463,123		452,340
Individually evaluated for impairment						0
Collectively evaluated for impairment						23,598,110
Loans	$ 24,409,030		24,409,030			23,598,110
Consumer Portfolio Segment [Member] | Other Consumer Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance			$ 179,070
Held for investment, allowance for credit loss						$ 179,070