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24. POST-EMPLOYMENT OBLIGATIONS (Details 10) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Pension plans and retirement supplement plans [member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Annual discount rate for present value of the actuarial obligation |  | 6.83% | 6.87% | 9.02%
Annual expected return on plan assets |  | 6.83% | 6.87% | 9.02%
Long-term annual inflation rate |  | 3.32% | 3.61% | 4.01%
Estimated future annual salary increases |  | 3.32% | 3.61% | 4.01%
General mortality table |  | AT-2000 M S10% D10% | AT-2000 M S10% D10% | AT-2000 M S10% D10%
Disability table |  | Not applicable | Not applicable | Not applicable
Disabled mortality table |  | AT-49 M | AT-49 M | AT 49 M
Real growth in contributions above inflation | [1] |  |  |
Health plan [member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Annual discount rate for present value of the actuarial obligation |  | 7.14% | 7.09% | 9.60%
Long-term annual inflation rate |  | 3.32% | 3.61% | 4.00%
General mortality table |  | AT-2000 M S10% D20% | AT-2000 M S10% D20% | AT-2000 M S10% D20%
Disability table |  | Álvaro Vindas D30% | Álvaro Vindas D30% | Álvaro Vindas D30%
Disabled mortality table |  | MI-85 F | MI-85 F | Winklevoss D30%
Real growth in contributions above inflation | [1] | 1.00% | 1.00% | 1.00%
Life insurance plan [member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Annual discount rate for present value of the actuarial obligation |  | 7.25% | 7.19% | 9.57%
Long-term annual inflation rate |  | 3.32% | 3.61% | 4.00%
Estimated future annual salary increases |  | 4.56% | 4.85% | 6.08%
General mortality table |  | AT-2000 M S10% D20% | AT-2000 M S10% D20% | AT-2000 M S10% D20%
Disability table |  | Álvaro Vindas D30% | Álvaro Vindas D30% | Álvaro Vindas D30%
Disabled mortality table |  | MI-85 F | MI-85 F | Winklevoss D30%
Real growth in contributions above inflation | [1] |  |  |
[1] | Starting in 2018, Company adopted the assumption of real growth of the contributions above inflation at the rate of 1% p.a.

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- Definition Actuarial assumption disability rate. + References No definition available. + Details
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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 The expected rate of salary increases 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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