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Note 3 - Loans and Allowance for Credit Losses - Financing Receivable, Troubled Debt Restructurings (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($)
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] | Interest Only Payments [Member]
amortized cost	$ 6,396
Percentage	4.40%
Commercial real estate owner-occupied (Month)	3 months
Commercial and industrial (Month)	3 months
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] | Extended Maturity [Member]
amortized cost	$ 6
Percentage	0.01%

X

- Definition

Duration of interest only payment.

+ References

No definition available.

+ Details

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
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X

- Definition

Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

+ References

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-Topic 310
-SubTopic 10
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X

- Definition

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

+ References

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-Topic 310
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