Note 7 - Stock-based Compensation - Stock Option Plan Cost (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Fair value of options vested | $ 0 | $ 0 | $ 173,000 | $ 193,000 |
| Intrinsic value of options exercised | 101,000 | 243,000 | 1,525,000 | 614,000 |
| Cash received from option exercises | 101,000 | 254,000 | 1,489,000 | 583,000 |
| Tax benefit from option exercises | 0 | 2,000 | 220,000 | 19,000 |
| Compensation cost | 150,000 | 96,000 | 251,000 | 163,000 |
| Tax benefit associated with compensation cost | $ 8,000 | $ 5,000 | $ 14,000 | $ 9,000 |
| X | ||||||||||
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of tax benefit from exercise of option under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of cash inflow from exercise of option under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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