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Note 20 - Regulatory Matters (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	May 31, 2021	Dec. 31, 2009
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
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval	$ 130.0				$ 130.0
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	0
Preferred Securities of Subsidiary Trust	48.3				$ 48.3	$ 47.6
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
Trust Preferred Securities Included in Tier One Capital	$ 48.3				$ 48.3	$ 47.6
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)					$ 1.4	$ 1.34	$ 1.26
O 2024 Q1 Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)				$ 0.35
Dividends Payable, Date Declared				Jan. 11, 2024
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)				$ 0.35
Dividends Payable, Date to be Paid				Mar. 13, 2024
Dividends Payable, Date of Record				Mar. 01, 2024
O 2024 Q2 Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)			$ 0.35
Dividends Payable, Date Declared			Apr. 11, 2024
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)			$ 0.35
Dividends Payable, Date to be Paid			Jun. 19, 2024
Dividends Payable, Date of Record			Jun. 07, 2024
O 2024 Q3 Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)		$ 0.36
Dividends Payable, Date Declared		Jul. 11, 2024
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)		$ 0.36
Dividends Payable, Date to be Paid		Sep. 18, 2024
O 2024 Q4 Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.36
Dividends Payable, Date Declared	Oct. 10, 2024
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 0.36
Dividends Payable, Date to be Paid	Dec. 18, 2024
Dividends Payable, Date of Record	Dec. 06, 2024

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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The maximum amount of restricted core elements allowed in tier one capital expressed as a percent.

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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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Trust preferred securities held by the trust that are included in Tier One Capital and subject to certain limitations.

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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.

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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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Aggregate dividends declared 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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Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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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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