Derivatives and Fair Value Measurements - Long-term debt (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Debt and Lease Obligation, Net | $ 335.2 | $ 336.4 |
| Carrying amount | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Total debt at par value | 339.1 | 340.8 |
| Less: Unamortized debt issuance costs | (3.9) | (4.4) |
| Debt and Lease Obligation, Net | 335.2 | 336.4 |
| Estimated fair value | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Estimated fair value | $ 605.8 | $ 557.8 |
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- Definition Amount of short-term and long-term debt and lease obligation. No definition available.
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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/exampleRef
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- Definition Amount of long-term debt and lease obligation, including portion classified as current. No definition available.
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. No definition available.
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