CREDIT LOSSES - GROSS RECEIVABLES AND RELATED ALLOWANCES (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Jun. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
Jun. 30, 2025 |
Dec. 31, 2024 |
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| Utility segment | ||||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||||
| Accounts receivable and unbilled revenues | $ 712.1 | $ 781.9 | ||||
| Allowance for credit losses | 35.0 | $ 37.7 | 39.7 | $ 31.7 | $ 32.9 | $ 46.9 |
| Accounts receivable and unbilled revenues, net | 677.1 | 742.2 | ||||
| Total accounts receivable, net - past due greater than 90 days | $ 33.1 | $ 33.0 | ||||
| Past due greater than 90 days - collection risk mitigated by regulatory mechanisms | 94.40% | 94.50% | ||||
| Amount of net accounts receivable with regulatory protections | $ 377.9 | |||||
| Percent of net accounts receivable with regulatory protections | 55.80% | |||||
| Other Segment | ||||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||||
| Accounts receivable and unbilled revenues | $ 0.0 | $ 0.0 |
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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/2009/role/commonPracticeRef
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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accounts receivable past due greater than 90 days No definition available.
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- Definition Amount of net accounts receivable and unbilled revenues with regulatory protections in place to mitigate the exposure to credit losses No definition available.
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- Definition Percent of accounts receivable past due greater than 90 days with regulatory mechanisms to mitigate collection risk No definition available.
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- Definition Percent of net accounts receivable and unbilled revenues with regulatory protections in place to mitigate the exposure to credit losses No definition available.
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