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- Definition

Financial Transmission Rights Fair Value Disclosure

+ References

No definition available.

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- Definition

Forward Power Contracts Fair Value Disclosure

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
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-Subparagraph (a)
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- Definition

Amount, after accumulated amortization, of debt discount.

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-Topic 835
-SubTopic 30
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 835
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-Topic 470
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- Definition

Amount of settlements 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 2
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Fair Value (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Fair Value (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Option, Quantitative Disclosures [Line Items]
Financial Transmission Rights Fair Value Disclosure	$ 393	$ 1,388
Forward Power Contracts Fair Value Disclosure	0	14,294
Investments, Fair Value Disclosure	3,646	3,552
Assets, Fair Value Disclosure	4,039	19,234
Investments, Fair Value Disclosure	3,646	3,552
Asset Retirement Obligation, Revision of Estimate	8,525	0
Asset retirement obligations	267,872		$ 249,930
Unamortized deferred financing costs	36,400		24,800
Unamortized debt discount	9,700		6,800
Financial Transmission Rights Fair Value Disclosure	393	1,388
Assets, Fair Value Disclosure	4,039	19,234
Derivative Financial Instruments, Liabilities
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	393	2,559	$ 1,388	$ 7,545
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(995)	(4,986)
Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	86	127
Investments, Fair Value Disclosure	86	127
Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	3,560	3,425
Investments, Fair Value Disclosure	3,560	3,425
Fair Value, Inputs, Level 3 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Financial Transmission Rights Fair Value Disclosure	393	1,388
Forward Power Contracts Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	0	0
Assets, Fair Value Disclosure	393	1,388
Investments, Fair Value Disclosure	0	0
Financial Transmission Rights Fair Value Disclosure	393	1,388
Assets, Fair Value Disclosure	393	1,388
Fair Value, Inputs, Level 3 [Member] \| Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Financial Transmission Rights Fair Value Disclosure	0	0
Forward Power Contracts Fair Value Disclosure	0	14,294
Investments, Fair Value Disclosure	0	0
Assets, Fair Value Disclosure	0	14,294
Investments, Fair Value Disclosure	0	0
Financial Transmission Rights Fair Value Disclosure	0	0
Assets, Fair Value Disclosure	0	14,294
Fair Value, Inputs, Level 2 [Member] \| Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Financial Transmission Rights Fair Value Disclosure	0	0
Forward Power Contracts Fair Value Disclosure	0	0
Investments, Fair Value Disclosure	3,646	3,552
Assets, Fair Value Disclosure	3,646	3,552
Investments, Fair Value Disclosure	3,646	3,552
Financial Transmission Rights Fair Value Disclosure	0	0
Assets, Fair Value Disclosure	3,646	3,552
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	86	127
Investments, Fair Value Disclosure	86	127
Fair Value, Inputs, Level 1 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	3,560	3,425
Investments, Fair Value Disclosure	3,560	$ 3,425
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Derivative, Notional Amount	$ 400,000