Derivative Instruments (Details) - BVESI $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) MWh	Dec. 31, 2021 USD ($)
Derivative instruments
Derivative Activity Volume \| MWh	216,471
Changes in the fair value of the derivative
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ 11,800
Purchase power contract
Changes in the fair value of the derivative
Balance, at beginning of the period	(4,441)	$ 1,537
Unrealized gain on purchased power contracts	7,406	5,978
Balance, at end of the period	$ 11,847	$ (4,441)
Minimum
Derivative instruments
Derivative, Term of Contract	3 years
Minimum \| Purchase power contract
Derivative instruments
Derivative, Term of Contract	3 years
Maximum
Derivative instruments
Derivative, Term of Contract	5 years
Maximum \| Purchase power contract
Derivative instruments
Derivative, Term of Contract	5 years

Derivative Activity Volume

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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.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19279-110258

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