Summary of Significant Accounting Principles (Details-2) - Columbia Units [Member] $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($)
Jointly Owned Utility Plant Interests [Line Items]
Net book value of property, plant, and equipment	$ 133.0
Impairment of Long-Lived Assets
Impairment of long-lived assets	$ 0.0

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.

No definition available.

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- Definition

Amount of loss (recovery of loss) related to a plant abandonment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 360
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 10.E)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479960/980-360-S99-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section 35
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481680/980-360-35-9

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- Definition

The present value amount of future cost recoveries that are probable and estimable related to plant abandonment's for regulated industries.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section 35
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481680/980-360-35-3

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- References

No definition available.

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