Segments - Assets (Details) - USD ($) $ in Thousands	Jun. 27, 2026	Dec. 31, 2025
Segment Reporting [Line Items]
Total assets	$ 510,422	$ 568,383
Operating Segments \| High Purity Cellulose
Segment Reporting [Line Items]
Total assets	395,656	446,521
Operating Segments \| Paperboard & High Yield Pulp
Segment Reporting [Line Items]
Total assets	101,927	101,787
Corporate & Other
Segment Reporting [Line Items]
Total assets	$ 12,839	$ 20,075

Amount of asset recognized for present right to economic benefit, classified as current.

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+ Details

- 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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+ Details