v3.25.4

Segment Information - Additional Information (Details) | 12 Months Ended
--- | ---
Dec. 31, 2025 Segment Customer Mill | Dec. 31, 2024 Customer | Dec. 31, 2023 Customer
Segment Reporting Information [Line Items] |  |  |
Number of pulp mills | Mill | 4 |  |
Number of reportable segments | Segment | 2 |  |
Segment Reporting, Measurement for Transactions Between Reportable Segments | Revenues between segments are accounted for at prices that approximate fair value. These include revenues from the sale of residual fiber from the solid wood segment to the pulp segment for use in the pulp production process and from the sale of residual fuel from the pulp segment to the solid wood segment for use in energy production. |  |
Segment Reporting Information, Description of Products and Services | The Company is managed based on the primary products it manufactures: pulp and solid wood |  |
Segment Reporting, Factors Used to Identify Entity's Reportable Segments | The Company is managed based on the primary products it manufactures: pulp and solid wood, whose operating results are regularly reviewed by the Company’s CODM to assess segment performance and to make decisions about resource allocation. |  |
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] | srt:ChiefExecutiveOfficerMember |  |
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description | The CODM uses net income (loss) before interest, tax, depreciation and amortization and impairments of long-lived assets (“Segment Operating EBITDA”) as the primary measure in its review of segment operating performance, using the measure to assess segment trends and identify strategies to improve the allocation of resources among the reportable segments. |  |
Segment Reporting, Change in Measurement Methods | The CODM uses net income (loss) before interest, tax, depreciation and amortization and impairments of long-lived assets (“Segment Operating EBITDA”) as the primary measure in its review of segment operating performance, using the measure to assess segment trends and identify strategies to improve the allocation of resources among the reportable segments. |  |
Number of customers accounting for 10% or more of sales | Customer | 0 | 0 | 0
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Minimum |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue major customer percentage | 10.00% |  |

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