Note 2 - Securities Available for Sale (Details Textual) Pure in Thousands	6 Months Ended
Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 315,000		$ 326,000
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 74,627,000		$ 78,719,000
Number of Securities of One Issuer Greater Than Ten Percent of Members' Equity	0		0
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 0
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable		Interest Receivable
Asset Pledged as Collateral [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 0		$ 0

The number of securities of any one issuer that is greater than 10% of members' equity.

No definition available.

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- Definition

Amount, after allowance for credit loss, of accrued interest 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 320
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-Name Accounting Standards Codification
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- Definition

Indicates line item in statement of financial position that includes accrued interest, after 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
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-URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A

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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/2003/role/disclosureRef
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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