Note 2 - Securities Available for Sale (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 0	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	35		35
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 0		$ 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	160,747,239		160,747,239		$ 140,307,447
Asset Pledged as Collateral [Member] \| Deposits [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	5,427,755		5,427,755		5,741,240
Asset Pledged as Collateral [Member] \| Securities Sold under Agreements to Repurchase [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 61,746		$ 61,746		$ 12,881,892
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Financing Receivable, Affirmed Commitment to Support, Percentage	100.00%		100.00%

Percentage of financing receivables that have affirmed commitment to support.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on 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/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Amount excluding accrued interest, of 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 326
-SubTopic 30
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-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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- Definition

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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