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30. EMPLOYEE BENEFITS (Details 16) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Disclosure of defined benefit plans [line items] |  |
General mortality table | Millennium Plan: AT-2012 segregated by gender Plan 35%: AT-2000 Male aggravated by 15% Supplementation: AT-2000 aggravated by 10% segregated by gender | Millennium Plan: AT-2000 smoothed down by 10% segregated by gender Plan 35%: AT-2000 Male aggravated by 15% Supplementation: AT-2000 aggravated by 10% segregated by gender
Inflation rate | 3.32% | 3.61%
Post-employment Healthcare Benefits [member] |  |
Disclosure of defined benefit plans [line items] |  |
General mortality table | AT 2000 segregated by gender | AT 2000 segregated by gender
Actuarial nominal discount rate | 6.53% | 6.78%
Inflation rate | 3.32% | 3.61%
Real increase in medical costs based on age (Aging Factor) | 0,5% - 3,00% real per year | 0,5% - 3,00% real per year
Nominal increase medical costs growth rate | 4.10% | 6.98%

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- Definition The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The expected rate of inflation that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Medical cost trend rate used as significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + 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 Represents the information about general mortality table. + References No definition available. + Details
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- Definition Real increase in medical costs based on age (Aging Factor) + References No definition available. + Details
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- Details
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