Sale of Businesses	9 Months Ended
Sep. 30, 2026
Discontinued Operations and Disposal Groups [Abstract]
Sale of Businesses	NOTE 3. _________________ SALE OF BUSINESSES Sale of Engineered Absorbent Materials Corporation On May 31, 2026, Domtar completed the sale of 100% of its shares in the Engineered Absorbent Materials Corporation ("EAM"), located in Jesup, Georgia. The Company completed the sale for a cash consideration of $8 million, resulting in a net loss of nil. Transfer of power generation assets On September 8, 2025, Domtar transferred certain power generation assets to Paper Excellence Canada Holdings Corporation ("PECHC"), an affiliated company, through the creation and sale of a special purpose entity, for consideration of $62 million tendered by PECHC through the issuance of interest-bearing notes, in the principal amounts of $47 million and $15 million (the "Agreement"). The notes issued by PECHC bear interest at 10% and are payable to Domtar no later than September 8, 2027. The notes are secured by a movable hypothec on the equity interests acquired by PECHC under the Agreement (see Note 10 "Closure and restructuring and impairment of long-lived assets" for more details). Sale of Espanola, Ontario mill On April 9, 2025, the Company signed a purchase agreement for the sale of its Espanola facility. On October 17, 2025, the Company completed the sale (see Note 10 “Closure and restructuring and impairment of long-lived assets” for more details). Sale of Forest Products Mauricie, Quebec sawmill On April 2, 2025, Domtar reached an agreement for the sale of the Forest Products Mauricie (“FPM”) sawmill. On July 1, 2025, the Company completed the sale for a cash consideration of $15 million, resulting in a gain of $9 million.

Sale of Businesses

9 Months Ended

Sep. 30, 2026

Discontinued Operations and Disposal Groups [Abstract]

NOTE 3.

_________________

SALE OF BUSINESSES

Sale of Engineered Absorbent Materials Corporation

On May 31, 2026, Domtar completed the sale of 100% of its shares in the Engineered Absorbent Materials Corporation ("EAM"), located in Jesup, Georgia. The Company completed the sale for a cash consideration of $8 million, resulting in a net loss of nil.

Transfer of power generation assets

On September 8, 2025, Domtar transferred certain power generation assets to Paper Excellence Canada Holdings Corporation ("PECHC"), an affiliated company, through the creation and sale of a special purpose entity, for consideration of $62 million tendered by PECHC through the issuance of interest-bearing notes, in the principal amounts of $47 million and $15 million (the "Agreement"). The notes issued by PECHC bear interest at 10% and are payable to Domtar no later than September 8, 2027. The notes are secured by a movable hypothec on the equity interests acquired by PECHC under the Agreement (see Note 10 "Closure and restructuring and impairment of long-lived assets" for more details).

Sale of Espanola, Ontario mill

On April 9, 2025, the Company signed a purchase agreement for the sale of its Espanola facility. On October 17, 2025, the Company completed the sale (see Note 10 “Closure and restructuring and impairment of long-lived assets” for more details).

Sale of Forest Products Mauricie, Quebec sawmill

On April 2, 2025, Domtar reached an agreement for the sale of the Forest Products Mauricie (“FPM”) sawmill. On July 1, 2025, the Company completed the sale for a cash consideration of $15 million, resulting in a gain of $9 million.