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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
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- Definition

Fair value portion of asset recognized for present right to economic benefit.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
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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

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- Definition

Amount of issuances 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://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
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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

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (b)
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
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-Section 50
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Fair Value (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Fair Value (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	$ 3,938	$ 3,552	$ 3,938	$ 3,552
Asset Retirement Obligation, Revision of Estimate			81,714	0
Asset retirement obligations, non-current	320,166		320,166			$ 249,930
Unamortized deferred financing costs	35,300		35,300			24,800
Unamortized debt discount	9,500		9,500			6,800
Financial Transmission Rights Fair Value Disclosure	2,817	1,388	2,817	1,388
Assets, Fair Value Disclosure	6,755	19,234	6,755	19,234
Forward Power Contracts Fair Value Disclosure	0	14,294	0	14,294
Derivative Financial Instruments, Liabilities
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	2,817	2,351	2,817	2,351	$ 3,968	$ 1,388	$ 3,294	$ 7,545
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances	0	0	3,811	3,624
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(1,151)	(943)	(2,382)	(8,818)
Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	83	127	83	127
Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	3,855	3,425	3,855	3,425
Fair Value, Inputs, Level 3 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0	0	0
Financial Transmission Rights Fair Value Disclosure	2,817	1,388	2,817	1,388
Assets, Fair Value Disclosure	2,817	1,388	2,817	1,388
Forward Power Contracts Fair Value Disclosure	0	0	0	0
Fair Value, Inputs, Level 3 [Member] \| Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0	0	0
Fair Value, Inputs, Level 3 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0	0	0
Financial Transmission Rights Fair Value Disclosure	0	0	0	0
Assets, Fair Value Disclosure	0	14,294	0	14,294
Forward Power Contracts Fair Value Disclosure	0	14,294	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	0	0
Fair Value, Inputs, Level 2 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	0	0	0	0
Fair Value, Inputs, Level 1 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	3,938	3,552	3,938	3,552
Financial Transmission Rights Fair Value Disclosure	0	0	0	0
Assets, Fair Value Disclosure	3,938	3,552	3,938	3,552
Forward Power Contracts Fair Value Disclosure	0	0	0	0
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	83	127	83	127
Fair Value, Inputs, Level 1 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	3,855	$ 3,425	3,855	$ 3,425
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Derivative, Notional Amount	$ 400,000		$ 400,000