Financial Instruments - Additional Information (Detail)	9 Months Ended	12 Months Ended
Financial Instruments - Additional Information (Detail)	Sep. 30, 2026 USD ($) MMBTU	Dec. 31, 2025 USD ($) MMBTU
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Financial instruments with fair values \| $	$ 0	$ 0
Natural Gas Purchase Commitments [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Natural gas purchase commitments volume	1,500,000
Natural Gas Purchase Commitments [Member] \| Level 2 [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Natural gas purchase commitments volume	0	0

- 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.

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