SUPPLEMENTARY FINANCIAL STATEMENT INFORMATION - Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials	$ 70	$ 69
Finished paper and pulp products	299	217
Operating supplies	124	122
Other	10	10
Total	$ 503	$ 418

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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Amount, after of valuation reserves and allowances, of inventory, classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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