Note 7 - Stock-based Compensation - Valuation Assumptions (Details) - $ / shares |
9 Months Ended | |
|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Weighted-average expected life of stock options (in years) (Year) | 6 years | 7 years 6 months |
| Weighted-average risk free interest rate | 3.98% | 4.50% |
| Weighted-average annualized volatility | 35.80% | 34.80% |
| Weighted-average dividend yields | 2.60% | 2.70% |
| Weighted-average fair value of options granted during the nine months ended September 30, 2026 (in dollars per share) | $ 15.96 | $ 17.9 |
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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