Note 7 - Subordinated Debentures and Other Borrowing Arrangements (Details Textual) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
Dec. 20, 2019	Mar. 31, 2026	Dec. 31, 2025
Federal Funds Purchased		$ 55,000	$ 60,000
Federal Funds Purchased, Average Rate Paid		3.75%	3.75%
Discount Window [Member]
Federal Reserve Bank Borrowings, Outstanding		$ 0	$ 0
Federal Reserve Bank [Member] \| Discount Window [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		981,000	853,900
Federal Home Loan Bank of San Francisco [Member]
Advance from Federal Home Loan Bank			0
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available		548,700	530,000
Federal Lines of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 209,000	$ 206,000
Subordinated Debt [Member]
Debt Instrument, Face Amount	$ 22,000
Debt Instrument, Term (Year)	10 years
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Debt Instrument, Basis Spread on Variable Rate	3.595%
Debt Instrument, Interest Rate, Effective Percentage		7.29%

Represents the amount of federal reserve bank borrowings outstanding.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Average rate paid on federal funds purchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph b
-Subparagraph (3)
-Publisher SEC

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Balance Type:	na
Period Type:	instant

- Definition

Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Period Type:	instant

- Details

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