Note 3 - Securities Held to Maturity (Details Textual)	12 Months Ended
Dec. 31, 2022 USD ($)	Sep. 30, 2023 USD ($)
Debt Securities, Available-for-Sale and Held-to-Maturity, Allowance for Credit Loss		$ 0
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	$ 77,427,309	$ 65,927,156
Held-to-Maturity, Securities in Unrealized Loss Positions		55
Other-than-temporary Impairment Loss, Debt Securities, Held-to-Maturity, before Tax	0
Asset Pledged as Collateral [Member] \| Federal Home Loan Bank Advances [Member]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	5,293,804	$ 1,709,280
Asset Pledged as Collateral [Member] \| Deposits [Member]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	$ 5,293,804	$ 5,079,376

Represents the number of held-to-maturity securities in unrealized loss positions.

No definition available.

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- Definition

Amount of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

+ Details

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- Definition

Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ 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 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-7A

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- Definition

Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at amortized cost (held-to-maturity), recognized in earnings and other comprehensive income (OCI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-8A

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- Details

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- Details

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- Details

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