Net financial results (Details) - BRL (R$) R$ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Financial expenses [Abstract]
Interest on loans, financing and debentures (1)			R$ (2,733,269)	R$ (1,743,417)
Amortization of transaction costs			(48,174)	(39,616)
Interest expenses on lease liabilities (2)			(230,308)	(222,185)
Other			(234,773)	(278,075)
Financial expenses			(3,246,524)	(2,283,293)
Financial income [Abstract]
Cash and cash equivalents and marketable securities			702,662	819,082
Other			119,450	62,023
Financial income			822,112	881,105
Results from derivative financial instruments [Abstract]
Income			7,015,340	824,285
Expenses			(662,835)	(5,349,163)
Derivative financial instruments, net	R$ 2,659,346	R$ (3,890,341)	6,352,505	(4,524,878)
Monetary and exchange rate variations, net [Abstract]
Exchange rate variations on loans, financing and debentures			9,147,254	(9,383,027)
Leases			322,483	(329,505)
Other assets and liabilities (3)			(1,276,652)	1,525,875
Monetary and exchange variations, net	R$ 2,988,799	R$ (6,487,329)	8,193,085	(8,186,657)
Net financial result			12,121,178	(14,113,723)
Interest costs capitalised			126,119	802,515
Reclassification to biological assets			R$ 133,133	R$ 104,137

The amount of income or cost associated with interest and other financing activities of the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

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The amount of exchange differences recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9. [Refer: At fair value [member]; Classes of financial instruments [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The gains resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

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The amount of interest costs that an entity incurs in connection with the borrowing of funds that are directly attributable to the acquisition, construction or production of a qualifying asset and which form part of the cost of that asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of interest expense on borrowings. [Refer: Interest expense; Borrowings]

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The amount of interest income on cash and cash equivalents. [Refer: Interest income; Cash and cash equivalents]

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The losses resulting from changes in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

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The amount of finance costs that the entity does not separately disclose in the same statement or note. [Refer: Finance costs]

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The amount of finance income that the entity does not separately disclose in the same statement or note. [Refer: Finance income]

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Amount of amortization expense attributable to debt issuance costs.

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The amount of costs associated with financing activities of the entity before gains (losses) on exchange differences.

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The amount of income associated with interest and other financing activities of the entity before gains (losses) on exchange differences.

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Financial expenses

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The amount of financial expenses attributable to interest expense on lease liabilities.

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Financial income

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The amount of exchange differences related to loans and financing, recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9.

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The amount of exchange differences related to other assets and liabilities, recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9.

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No definition available.

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The amount of gains (losses) on exchange rate variation net, relating to leases.

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Monetary and exchange rate variations, net

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Reclassification to biological assets

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Results from derivative financial instruments

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