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17. CONCESSION CONTRACT ASSETS (Details) - BRL (R$) R$ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |  |
Contract assets | R$ 2,005 | R$ 1,729 |
Current | 172 | 131 |
Non current | 1,833 | 1,598 |
Distribution - Infrastructure Assets Under Construction [Member] |  |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |  |
Contract assets | 740 | 518 |
Gas - Infrastructure Assets Under Construction [Member] |  |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |  |
Contract assets | 68 | 82 |
Transmission - Assets Reincorporated Into The Assets Remuneration Base [Member] |  |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |  |
Contract assets | 348 | 492 |
Transmission - Assets Remunerated by Tariff [Member] |  |  |
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items] |  |  |
Contract assets | R$ 849 | R$ 637 |

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- Definition The amount of an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer, when that right is conditioned on something other than the passage of time (for example, the entity’s future performance). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2019-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_105&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2019-01-01 -Paragraph 116 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_116_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of current contract assets. [Refer: Contract assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2019-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_105&doctype=Standard -URIDate 2019-03-27 + 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 amount of non-current contract assets. [Refer: Contract assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2019-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_105&doctype=Standard -URIDate 2019-03-27 + Details
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- Details
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- Details
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