BIOLOGICAL ASSETS - Changes (Details) - BRL (R$) R$ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Changes in balances of biological assets
Balance, beginning of the year	R$ 11,161,210	R$ 10,571,499	R$ 10,571,499
Addition	1,611,674		3,392,975
Depletion	(1,489,460)		(3,094,742)
Transfers	28,292		(23,471)
Gain on fair value adjustment	564,533	R$ 173,733	466,484
Disposal	(136,044)		(93,847)
Other write-offs	(19,348)		(57,688)
Balance, end of the year	R$ 11,720,857		R$ 11,161,210
Effective area of forest from the year of planting	3 years
Minimum
Changes in balances of biological assets
Average cycle of forest formation	6 years
Maximum
Changes in balances of biological assets
Average cycle of forest formation	7 years

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

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The gains (losses) arising from changes in fair value less costs to sell of biological assets due to both physical and price changes in the market. [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 period of harvest cycle with productivity and area of plantation for determining the fair value of biological assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

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Period for effective area for forest from the year of planting for determining the fair value of biological assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

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

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