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18. INTANGIBLE ASSETS (Details Narrative) - BRL (R$) R$ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Capitalized borrowing costs | R$ 1 | R$ 2 |  | R$ 4 |
Annual average amortization rate | 4.05% |  |  |  |
Assets | R$ 4,058 |  |  |  |
impairment reversal | 14 | 22 |  |  |
Intangible assets | 11,810 | 11,624 | [1] | R$ 10,777 | R$ 11,156
Gasmig [member] |  |  |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Intangible assets | 412 | 427 |  |  |
Parajuru and Volta do Rio [member] |  |  |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Intangible assets | 128 | 127 |  |  |
concession contract assets to intangible assets [member] |  |  |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Assets | 906 | 685 |  |  |
plant and equipment to intangible assets [member] |  |  |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Assets | 2 | 4 |  |  |
concession financial asset to intangible assets [member] |  |  |  |  |
Disclosure of detailed information about intangible assets [line items] |  |  |  |  |
Assets | R$ 5 | R$ 23 |  |  |
[1] | See note 2.8.

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- Definition The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_25&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 35H -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_35H&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 35I -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_35I&doctype=Standard -URIDate 2020-01-01 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 35M -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_35M&doctype=Standard -URIDate 2020-01-01 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 35N -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_35N&doctype=Standard -URIDate 2020-01-01 + Details
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