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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 |  |

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- 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. + References No definition available. + Details
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