Goodwill (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
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| Changes in Carrying Amount of Goodwill | |||
| Goodwill | $ 52.5 | $ 52.5 | $ 52.5 |
| Impairment Losses | 0.0 | 0.0 | |
| Corporate and Other [Member] | |||
| Changes in Carrying Amount of Goodwill | |||
| Goodwill | 37.1 | 37.1 | 37.1 |
| Impairment Losses | 0.0 | 0.0 | |
| Generation and Marketing [Member] | |||
| Changes in Carrying Amount of Goodwill | |||
| Goodwill | 15.4 | 15.4 | $ 15.4 |
| Impairment Losses | $ 0.0 | $ 0.0 | |
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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