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Derivatives - Narrative (Details)	9 Months Ended
	Sep. 30, 2025 USD ($) Boe MWh t	Dec. 31, 2024 USD ($)
Derivative [Line Items]
Restricted cash | $	$ 0	$ 0
Fixed To Variable London Metals Exchange Swap
Derivative [Line Items]
Open position to offset fixed prices (in tonnes)	49,800
MWP Forward Financial Sales Contracts
Derivative [Line Items]
Open position to offset fixed prices (in tonnes)	83,400
Fixed For Floating Swaps
Derivative [Line Items]
Open position to offset fixed prices (in tonnes)	272
HFO Price Swaps
Derivative [Line Items]
Derivative liability (in MwH) | Boe	280,000
Indiana Hub Power Price Swaps
Derivative [Line Items]
Derivative liability (in MwH) | MWh	913,680

X

- 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/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

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Nominal mass used to calculate payments on a derivative instrument.

+ References

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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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