Biological assets - Roll-forward of biological assets (Details) - BRL (R$) R$ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Disclosure of reconciliation of changes in biological assets [line items]
Opening Balance	R$ 22,283,001	R$ 18,278,582	R$ 18,278,582
Additions from purchases, biological assets	6,281,750		7,180,450
Additions of merged companies			366,785
Depletions	(3,936,128)		(4,831,916)
Transfers	15,233		102,790
Gain (loss) on fair value adjustments	73,248	R$ (539,003)	(1,431,530)
Disposals	(23,383)		(130,922)
Write-offs	(101,764)		(114,298)
Closing Balance	R$ 24,445,461		R$ 22,283,001

The amount of additions to biological assets resulting from purchases. [Refer: Biological assets]

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The amount of additions to biological assets, other than those acquired through business combinations. [Refer: Total for all business combinations [member]; Biological assets]

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The decrease in biological assets due to the detachment of produce from the assets or the cessation of the assets' life processes. [Refer: Biological assets]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The decrease in biological assets resulting from disposals. [Refer: Biological assets]

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The increase (decrease) in biological assets resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Biological assets]

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The amount of non-current biological assets. [Refer: Biological assets]

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The increase (decrease) in biological assets resulting from transfers.

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