Note 8 - Deposits (Details Textual) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Time Deposits, at or Above FDIC Insurance Limit	$ 164.2	$ 174.4
Deposits, Public Fund	113.6	100.8
Letters of Credit Outstanding, Amount	60.0
Deposits, Funds Held by Federally Recognized Tribes	31.3	20.1
Asset Pledged as Collateral [Member] \| Funds Held by Federally Recognized Tribes [Member]
Debt Securities	40.7	22.8
Federal Home Loan Bank of Des Moines [Member]
Letters of Credit Outstanding, Amount	$ 60.0	$ 60.0

Represents funds held by federally recognized tribes as deposits.

No definition available.

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- Definition

Amount of public fund deposit liabilities.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), 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 net income (trading).

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Balance Type:	debit
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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- Details

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Period Type:

- Details

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