Note 4 - Loans - Schedule of Allowance for Credit Loss (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Beginning balance	$ 2,590,950	$ 2,747,949	$ 2,620,949	$ 2,785,949	$ 2,785,949
Provision for (recovery) of credit losses	(50,000)	0	(79,999)	(38,000)
Loans charged off	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	2,540,950	2,747,949	2,540,950	2,747,949	2,620,949
Commercial and Industrial [Member]
Beginning balance	24,340	33,221	20,000	22,000	22,000
Provision for (recovery) of credit losses	(6,563)	536	(2,223)	11,757
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	17,777	33,757	17,777	33,757	20,000
Consumer Portfolio Segment [Member]
Beginning balance	223	0	0	0	0
Provision for (recovery) of credit losses	(36)	0	187	0
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	187	0	187	0	0
Real Estate Loan [Member] \| Residential Portfolio Segment [Member]
Beginning balance	1,660,885	1,836,909	1,680,949	1,851,969	1,851,969
Provision for (recovery) of credit losses	(41,284)	(10,371)	(61,348)	(25,431)
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	1,619,601	1,826,538	1,619,601	1,826,538	1,680,949
Real Estate Loan [Member] \| Commercial Real Estate Portfolio Segment [Member]
Beginning balance	533,874	456,898	508,000	437,180	437,180
Provision for (recovery) of credit losses	22,684	5,417	48,558	25,135
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	556,558	462,315	556,558	462,315	508,000
Real Estate Loan [Member] \| Multi-Family Real Estate [Member]
Beginning balance	278,916	315,495	289,000	317,300	317,300
Provision for (recovery) of credit losses	9,125	(2,274)	(959)	(4,079)
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	288,041	313,221	288,041	313,221	289,000
Real Estate Loan [Member] \| Construction Loans [Member]
Beginning balance	92,712	105,426	123,000	157,500	157,500
Provision for (recovery) of credit losses	(33,926)	6,692	(64,214)	(45,382)
Loans charged off	0	0	0	0	0
Recoveries	0	0	0	0
Total ending allowance balance	$ 58,786	$ 112,118	$ 58,786	$ 112,118	$ 123,000

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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