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v3.23.1

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Public Utilities, General Disclosures [Line Items] |  |
Regulatory Deferral - Joint Venture | $ 4.4 | $ 2.9
Columbia Of Ohio |  |
Public Utilities, General Disclosures [Line Items] |  |
Public Utilities, Requested Rate Increase (Decrease), Percentage | 21.30% |
Public Utilities, Requested Rate Increase (Decrease), Amount | $ 221.4 |

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- Definition Regulatory Deferral - Joint Venture + References No definition available. + Details
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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. + References No definition available. + Details
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- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Percentage of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |