Capital Stock (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
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| Capital Stock [Abstract] | |||||
| Percent of stock owned by active and retired employees | 100.00% | ||||
| Percent of shares held in voting trust | 68.00% | 68.00% | |||
| Common stock, stated value per share | $ 20.00 | $ 20.00 | $ 20.00 | ||
| Cash dividends | $ 9.9 | $ 9.7 | $ 19.8 | $ 19.5 | |
| Preferred stock shares authorized | 10,000,000 | 10,000,000 | |||
| Preferred stock par or stated value per share (USD per share) | $ 0.01 | $ 0.01 | |||
| Preferred stock outstanding (in shares) | 0 | 0 | 0 | ||
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- Definition The percentage of common stock held in the Voting Trust No definition available.
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- Definition Stockholders' Equity Note, Percent of Entity Owned by Current and Retired Employees No definition available.
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- Definition Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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