Note 4 - Allowance for Credit Losses - Troubled Debt Restructurings (Details) - Real Estate 1 [Member] - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Contractual Interest Rate Reduction [Member]
Modification amount	$ 188	$ 380
Modification percent	0.16%	0.01%
Contractual Interest Rate Reduction [Member] \| Commercial and Industrial Loans [Member]
Modification amount	$ 188	$ 380
Modification percent	0.16%	0.01%
Modification, interest rate decrease	4.00%
Contractual Interest Rate Reduction [Member] \| Commercial and Industrial Loans [Member] \| Maximum [Member]
Modification, interest rate decrease		4.00%
Principal Forgiveness [Member]
Modification amount		$ 1,682
Modification percent		0.17%
Principal Forgiveness [Member] \| Commercial and Industrial Loans [Member]
Modification amount		$ 1,682
Modification percent		0.17%
Modification, deferral term (Month)		3 months

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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-Topic 310
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period of payment deferral of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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Balance Type:	na
Period Type:	instant

- Definition

Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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Balance Type:
Period Type: