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LONG-TERM INCENTIVE PLANS - Restricted Shares and Performance Shares (Details) - Restricted Shares and Performance Shares R$ in Thousands | 12 Months Ended
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Dec. 31, 2020 BRL (R$) EquityInstruments shares | Dec. 31, 2019 BRL (R$) EquityInstruments | Dec. 31, 2018 BRL (R$) EquityInstruments
LONG-TERM INCENTIVE PLANS |  |  |
Balance, beginning of year | 13,018,407 | 14,261,501 | 18,975,084
Granted | 3,146,696 | 2,647,995 | 2,411,345
Cancelled | (1,777,100) | (2,104,754) | (3,150,635)
Exercised | (1,918,669) | (1,786,335) | (3,974,293)
Balance, end of year | 12,469,334 | 13,018,407 | 14,261,501
Expense from equity-settled long-term incentive plan | R$ | R$ 62,801 | R$ 43,895 | R$ 41,186
Awards granted in 2016 and prior |  |  |
LONG-TERM INCENTIVE PLANS |  |  |
Grace period | 5 years |  |
Awards granted in 2017 and later |  |  |
LONG-TERM INCENTIVE PLANS |  |  |
Grace period | 3 years |  |
Preferred shares |  |  |
LONG-TERM INCENTIVE PLANS |  |  |
Treasury shares | shares | 16,799,758 |  |

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- Definition The amount of expense arising from equity-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions in which goods or services received did not qualify for recognition as assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 51 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_51_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
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