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FINANCIAL INSTRUMENTS - Net investment hedge (Details) R$ in Thousands, $ in Billions | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2020 BRL (R$) | Dec. 31, 2019 BRL (R$) | Dec. 31, 2018 BRL (R$)
Net investment hedge |  |  |  |
Gain (loss) on net investment hedge, recognized in OCI |  | R$ (2,504,914) | R$ (322,948) | R$ (1,491,534)
Ten/Thirty Years Bonds |  |  |  |
Net investment hedge |  |  |  |
Gain (loss) on net investment hedge, recognized in income |  |  | R$ (322,948,000) |
Ten/Thirty Years Bonds | Hedges of net investment in foreign operations |  |  |  |
Net investment hedge |  |  |  |
Gain (loss) on net investment hedge, recognized in OCI | $ | $ 2.1 |  |  |
Gain (loss) on net investment hedge, recognized in income |  | R$ (2,504,914,000) |  |

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- Definition The gains (losses) recognised in other comprehensive income on hedges of net investments in foreign operations, net of tax. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 39 -IssueDate 2020-01-01 -Paragraph 102 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=39&code=ifrs-tx-2020-en-r&anchor=para_102_a&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24C -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24C_b_i&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24E -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24E_a&doctype=Standard -URIDate 2020-01-01 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 91 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_91_a&doctype=Standard -URIDate 2020-01-01 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 9 -IssueDate 2020-01-01 -Paragraph 6.5.13 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=9&code=ifrs-tx-2020-en-r&anchor=para_6.5.13_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of reclassification adjustments related to hedges of net investments in foreign operations, net of tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 92 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_92&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 39 -IssueDate 2020-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=39&code=ifrs-tx-2020-en-r&anchor=para_102&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24C -Subparagraph b -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24C_b_iv&doctype=Standard -URIDate 2020-01-01 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24E -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24E_a&doctype=Standard -URIDate 2020-01-01 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 9 -IssueDate 2020-01-01 -Paragraph 6.5.14 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=9&code=ifrs-tx-2020-en-r&anchor=para_6.5.14&doctype=Standard -URIDate 2020-01-01 + Details
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