Summary of Significant Accounting Principles (Details-2) - Columbia Units [Member] $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Jointly Owned Utility Plant Interests [Line Items]
Net book value of property, plant, and equipment	$ 161,600
Impairment of Long-Lived Assets
Impairment of long-lived assets	$ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 10.E)
-URI http://asc.fasb.org/extlink&oid=122136288&loc=d3e660019-123033

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section 35
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6500292&loc=d3e45741-110387

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section 35
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6500292&loc=d3e45591-110387

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- References

No definition available.

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