Stock Plans: (Assumptions Used for Performance Share Units) (Details) - Performance Shares |
12 Months Ended | ||
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Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Average risk-free interest rate | 4.20% | 4.10% | 1.70% |
| Average expected volatility | 19.90% | 24.30% | 28.30% |
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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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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