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26. POST-EMPLOYMENT OBLIGATIONS (Details 3) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of fair value of plan assets [line items] |  |  |
Cost of current service | R$ 18 | R$ 15 | R$ 19
Interest on the actuarial obligation | 1,213 | 1,161 | 1,246
Expected return on the assets of the Plan | (767) | (771) | (810)
Past service cost |  |  | (619)
Expense according to actuarial calculation | 464 | 405 | (164)
Pension Plans and Retirement Supplement Plans [Member] |  |  |
Disclosure of fair value of plan assets [line items] |  |  |
Cost of current service | 1 | 4 | 5
Interest on the actuarial obligation | 963 | 959 | 980
Expected return on the assets of the Plan | (767) | (771) | (810)
Past service cost |  |  |
Expense according to actuarial calculation | 197 | 192 | 175
Health Plan [Member] |  |  |
Disclosure of fair value of plan assets [line items] |  |  |
Cost of current service | 14 | 10 | 11
Interest on the actuarial obligation | 208 | 172 | 178
Expected return on the assets of the Plan |  |  |
Past service cost |  |  |
Expense according to actuarial calculation | 222 | 182 | 189
Dental Plan [Member] |  |  |
Disclosure of fair value of plan assets [line items] |  |  |
Cost of current service |  | 0 |
Interest on the actuarial obligation | 5 | 4 | 3
Expected return on the assets of the Plan |  |  |
Past service cost |  |  |
Expense according to actuarial calculation | 5 | 4 | 3
Life Insurance [Member] |  |  |
Disclosure of fair value of plan assets [line items] |  |  |
Cost of current service | 2 | 1 | 3
Interest on the actuarial obligation | 38 | 26 | 85
Expected return on the assets of the Plan |  |  |
Past service cost |  |  | (619)
Expense according to actuarial calculation | R$ 40 | R$ 27 | R$ (531)

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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_141_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 141 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_141_d&doctype=Standard -URIDate 2019-03-27 + Details
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