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Note 4 - Loans - Schedule of Financing Receivables by Collateral (Details) - USD ($)	Sep. 30, 2025	Dec. 31, 2024
Total loans	$ 671,771,935	$ 714,337,185
Real Estate [Member]
Total loans	20,457,619	13,962,695
Other Collateral [Member]
Total loans	0	0
Commercial and Industrial [Member]
Total loans	3,703,476	6,163,747
Commercial and Industrial [Member] | Other Collateral [Member]
Total loans	0	0
Consumer Portfolio Segment [Member]
Total loans	64,336	80,955
Real Estate Loan [Member] | Residential Portfolio Segment [Member]
Total loans	449,596,294	472,747,542
Real Estate Loan [Member] | Residential Portfolio Segment [Member] | Real Estate [Member]
Total loans	2,502,938	1,863,957
Real Estate Loan [Member] | Residential Portfolio Segment [Member] | Other Collateral [Member]
Total loans	0	0
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member]
Total loans	122,811,801	118,008,866
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate [Member]
Total loans	7,060,968	1,205,025
Real Estate Loan [Member] | Commercial Real Estate Portfolio Segment [Member] | Other Collateral [Member]
Total loans	0	0
Real Estate Loan [Member] | Multi-Family Real Estate [Member]
Total loans	70,364,169	74,152,418
Real Estate Loan [Member] | Multi-Family Real Estate [Member] | Other Collateral [Member]
Total loans	0	0
Real Estate Loan [Member] | Construction Loans [Member]
Total loans	25,231,859	43,183,657
Real Estate Loan [Member] | Construction Loans [Member] | Real Estate [Member]
Total loans	10,893,713	10,893,713
Real Estate Loan [Member] | Construction Loans [Member] | Other Collateral [Member]
Total loans	0	0
Real Estate Loan [Member] | Commercial and Industrial [Member]
Total loans	3,703,476	6,163,747
Consumer Loans [Member] | Consumer Portfolio Segment [Member]
Total loans	64,336	80,955
Consumer Loans [Member] | Consumer Portfolio Segment [Member] | Other Collateral [Member]
Total loans	$ 0	$ 0

X

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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