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Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Public Utilities, General Disclosures [Line Items]
Depreciation, Nonproduction	$ (19.0)	$ (2.2)	$ (9.7)	$ (4.5)
Customer Refund Liability, Current	$ 12.4		$ 12.4
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

Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

+ References

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- Definition

The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-1

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- Definition

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

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- Definition

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

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