CONDENSED BALANCE SHEETS (PARENTHETICAL) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Accounts receivable and unbilled revenues, reserves | $ 7.8 | $ 7.8 |
| Property, plant, and equipment, accumulated depreciation and amortization | $ 2,352.9 | $ 2,320.2 |
| Common stock, par value (in dollars per share) | $ 4 | $ 4 |
| Common stock, shares authorized | 32,000,000 | 32,000,000 |
| Common stock, shares issued | 23,896,962 | 23,896,962 |
| Common stock, shares outstanding | 23,896,962 | 23,896,962 |
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- Definition The maximum number of common shares 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 Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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