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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

X

- Definition

Regulatory Deferral - Joint Venture

+ References

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X

- 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.

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- Definition

Percentage of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

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- Details

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