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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

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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

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- Definition

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

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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.

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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

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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

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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
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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

Fair value portion of liabilities pertaining to principal and customer trading transactions, or which may be incurred with the objective of generating a profit from short-term fluctuations in price as part of an entity's market-making, hedging and proprietary trading. Examples include, but are not limited to, short positions in securities, derivatives and commodities.

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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, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	$ 4,833	$ 4,428	$ 4,833	$ 4,428
Asset Retirement Obligation, Revision of Estimate			37,844	91,996
Asset retirement obligations, non-current	549,999	422,996	549,999	422,996		$ 532,463
Financial Transmission Rights Fair Value Disclosure	4,947	1,584	4,947	1,584
Assets, Fair Value Disclosure	9,825	6,012	9,825	6,012
Financial and Nonfinancial Liabilities, Fair Value Disclosure	2,743	0	2,743	0
Trading Liabilities, Fair Value Disclosure	2,743	0	2,743	0
Derivative Financial Instruments, Liabilities
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	4,947	2,972	4,947	2,972	$ 6,584	$ 1,584	$ 4,304	$ 1,526
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances	0	0	7,237	4,718
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(1,637)	(1,332)	(3,874)	(3,272)
Money Market Funds [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	144	104	144	104
Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	4,689	4,324	4,689	4,324
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	4,947	1,584	4,947	1,584
Assets, Fair Value Disclosure	4,947	1,584	4,947	1,584
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0	0	0
Trading Liabilities, 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	45	0	45	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	2,743	0	2,743	0
Trading Liabilities, Fair Value Disclosure	2,743	0	2,743	0
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	4,833	4,428	4,833	4,428
Financial Transmission Rights Fair Value Disclosure	0	0	0	0
Assets, Fair Value Disclosure	4,833	4,428	4,833	4,428
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0	0	0
Trading Liabilities, 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	144	104	144	104
Fair Value, Inputs, Level 1 [Member] \| Mutual Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments, Fair Value Disclosure	$ 4,689	$ 4,324	$ 4,689	$ 4,324