Inventories (Details) - BRL (R$) R$ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Inventories [Line Items]
Current finished goods
Current work in progress	147,446	135,380
Spare parts and other	1,475,399	1,302,534
(-) Expected losses	(104,209)	(97,934)
Inventories	8,955,941	7,962,324
Pulp \| Country of domicile
Inventories [Line Items]
Current finished goods	802,892	801,623
Pulp \| Foreign countries
Inventories [Line Items]
Current finished goods	2,049,974	1,510,985
Paper \| Country of domicile
Inventories [Line Items]
Current finished goods	707,612	561,409
Paper \| Foreign countries
Inventories [Line Items]
Current finished goods	478,441	362,027
Wood
Inventories [Line Items]
Current work in progress	2,297,789	2,287,406
Operating supplies and packaging
Inventories [Line Items]
Current work in progress	R$ 1,100,597	R$ 1,098,894

A classification of current inventory representing the amount of goods that have completed the production process and are held for sale in the ordinary course of business. [Refer: Inventories]

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The amount of current inventories. [Refer: Inventories]

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A classification of current inventory representing the amount of interchangeable parts that are kept in an inventory and are used for the repair or replacement of failed parts. [Refer: Inventories]

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A classification of current inventory representing the amount of assets currently in production, which require further processes to be converted into finished goods or services. [Refer: Current finished goods; Inventories]

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The amount of an allowance account used to record impairments to financial assets due to credit losses.

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Inventories [Line Items]

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