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EQUITY - Common and preferred shares outstanding (Details) - shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
EQUITY |  |  |
Shares exercise period, excluding public offerings | 30 days |  |
Shares exercise period for public offering | 10 days |  |
Common shares |  |  |
EQUITY |  |  |
Authorized capital | 1,500,000,000 |  |
Reconciliations of common and preferred outstanding shares |  |  |
Balance at beginning of the year | 571,929,945 | 571,929,945 | 571,929,945
Balance at end of period | 571,929,945 | 571,929,945 | 571,929,945
Preferred shares |  |  |
EQUITY |  |  |
Authorized capital | 3,000,000,000 |  |
Reconciliations of common and preferred outstanding shares |  |  |
Balance at beginning of the year | 1,127,010,827 | 1,124,233,755 | 1,137,327,184
Acquisition of Treasury shares |  |  | (16,000,000)
Exercise of stock options | 2,220,660 | 2,777,072 | 1,597,235
Transfer of shares |  |  | 1,309,336
Balance at end of period | 1,129,231,487 | 1,127,010,827 | 1,124,233,755

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- Definition The increase (decrease) in the number of shares outstanding resulting from exercise of stock options. + References No definition available. + Details
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- Definition The increase (decrease) in the number of shares outstanding resulting from treasury share transactions. + References No definition available. + Details
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- Definition Maximum term of preference share rights for offering that is not a public offering. + References No definition available. + Details
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- Definition Term of preference share rights for public offering, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The decrease in the number of shares outstanding resulting from purchase of treasury shares. + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The number of shares authorised. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 79 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_79_a_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The number of shares that have been authorised and issued, reduced by treasury shares held. [Refer: Treasury shares] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 79 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_79_a_iv&doctype=Standard -URIDate 2020-01-01 + Details
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- Details
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