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Note 10 - Stock-based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2023
Notes Tables |
Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] |
|  |  |  |  |  | Weighted |
|  |  |  |  |  | Average |
|  | Shares |  |  | Fair Value |
Nonvested at beginning of year |  |  | 374,771 |  |  | $ | 30.49 |
Granted |  |  | 95,084 |  |  |  | 40.23 |
Vested |  |  | (109,414 | ) |  |  | 27.01 |
Forfeited |  |  | (4,551 | ) |  |  | 28.70 |
Nonvested at end of year |  |  | 355,890 |  |  | $ | 34.18 |
Share-Based Payment Arrangement, Option, Activity [Table Text Block] |
|  |  |  |  |  | Weighted |
|  |  |  |  |  | Average |
|  |  |  |  |  | Exercise |
|  | Shares |  |  | Price |
Outstanding at beginning of year |  |  | 5,000 |  |  | $ | 36.22 |
Granted |  |  | 0 |  |  |  | 0.00 |
Exercised |  |  | 0 |  |  |  | 0.00 |
Forfeited or expired |  |  | (5,000 | ) |  |  | 34.89 |
Outstanding at end of year |  |  | 0 |  |  | $ | 0 |
Options exercisable at year end |  |  | 0 |  |  | $ | 0 |
Schedule of Share-based Compensation Shares Authorized Under Stock Option Plans Information Related to Option Outstanding [Table Text Block] |
|  | 2022 |  |  | 2021 |
Minimum exercise price |  | $ | 36.22 |  |  | $ | 27.66 |
Maximum Exercise Price |  |  | 36.22 |  |  |  | 36.22 |
Average Remaining Option Term |  |  | 0.9 |  |  |  | 1.7 |
Schedule of Share Based Compensation Arrangement by Share Based Payment Award Options Information Related to Stock Option Grants and Exercised [Table Text Block] |
(Dollars in thousands) |  | 2022 |  |  | 2021 |
Aggregate intrinsic value of stock options exercised |  | $ | 16 |  |  | $ | 13 |
Cash received from stock option exercises |  |  | 36 |  |  |  | 50 |
Tax benefit realized from stock option exercises |  |  | 0 |  |  |  | 0 |
Weighted average per share fair value of stock options granted |  |  | NA |  |  |  | NA |
Corporate and Bank Board Members [Member] |
Notes Tables |
Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block] |
|  |  |  |  |  | Total Cost |  |
Grant Year |  | Shares Granted |  |  | (in thousands) |  | Covered Period
2020 |  |  | 17,716 |  |  | $ | 394 |  | June 1, 2020 - May 31, 2021
2021 |  |  | 10,489 |  |  |  | 344 |  | June 1, 2021 - May 31, 2022
2022 |  |  | 11,166 |  |  |  | 359 |  | June 1, 2022 - May 31, 2023
2023 |  |  | 11,529 |  |  |  | 350 |  | June 1, 2023 - May 31, 2024

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