Derivative Instruments (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) MWh	Mar. 31, 2021 USD ($)
Commodity Contract
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at end of the period	$ (7,000)
GSWC
Derivative Instruments, Gain (Loss) [Line Items]
Description of derivative activity volume \| MWh	311,163
GSWC \| Minimum \| Commodity Contract
Derivative Instruments, Gain (Loss) [Line Items]
Term of derivative contract	3 years
GSWC \| Maximum \| Commodity Contract
Derivative Instruments, Gain (Loss) [Line Items]
Term of derivative contract	5 years
BVESI \| Commodity Contract
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of the period	$ 4,441	$ (1,537)
Unrealized gains on purchased power contracts	2,579	2,761
Fair value at end of the period	$ 7,020	$ 1,224

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

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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

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- Definition

Amount of unrealized gain (loss) recognized in income for derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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=117815213&loc=d3e19207-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258

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