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Note 13 - Regulatory Matters (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	May 31, 2021	Dec. 31, 2009
Maximum Restricted Core Element Allowed in Tier One Capital Percent					25.00%
Maximum Level of Consolidated Aggregate Assets Allowing for Inclusion of Trust Preferred Securities in Tier One Capital									$ 15,000.0
Capital Conservation Buffer	2.50%				2.50%
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy to Risk Weighted Assets	0.07				0.07
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.085				0.085
Capital Required for Capital Adequacy to Risk Weighted Assets	0.105				0.105
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 0.38			$ 0.36	$ 1.12	$ 1.06
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 6.8				$ 6.8
Stock Repurchase Program, Authorized Amount								$ 20.0
Stock Repurchased During Period, Shares (in shares)					0
O 2025 Q1 Dividends [Member]
Dividends Payable, Date Declared			Jan. 16, 2025
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)			$ 0.37
Dividends Payable, Date to be Paid			Mar. 19, 2025
Dividends Payable, Date of Record			Mar. 07, 2025
O 2025 Q2 Dividends [Member]
Dividends Payable, Date Declared		Apr. 17, 2025
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)		$ 0.37
Dividends Payable, Date to be Paid		Jun. 18, 2025
Dividends Payable, Date of Record		Jun. 06, 2025
O 2025 Q3 Dividends [Member]
Dividends Payable, Date Declared	Jul. 17, 2025
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 0.38
Dividends Payable, Date to be Paid	Sep. 17, 2025
Dividends Payable, Date of Record	Sep. 05, 2025
Tier One Capital [Member]
Preferred Securities of Subsidiary Trust	$ 48.8				$ 48.8		$ 48.3

X

- Definition

An additional amount held in risk-based capital designed to ensure that banks build up capital buffers outside periods of stress which can be drawn down as losses are incurred. The requirement is based on simple capital conservation rules designed to avoid breaches of minimum capital requirements.

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The minimum common equity tier one capital ratio (common equity tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under the Dodd-Frank Act.

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Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies.

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Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

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-Topic 505
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-Section 50
-Paragraph 4
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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Date the declared dividend will be paid, in YYYY-MM-DD format.

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Date the dividend to be paid was declared, in YYYY-MM-DD format.

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Amount remaining authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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