Concession Financial Assets and Liabilities - Summary of Financial Assets and Liabilities of Concession (Detail) - BRL (R$) R$ in Millions	Dec. 31, 2017	Dec. 31, 2016
Financial assets of the concession
Financial assets	R$ 7,453	R$ 5,701
Current assets	848	730
Non-current assets	6,605	4,971
Financial liabilities of the concession
Current liabilities	415	482
Non-current liabilities		323
CVA and Other Financial Components in Tariff Adjustments [member]
Financial liabilities of the concession
CVA (Portion A Compensation) Account and Other Financial Components in tariff adjustments	415	805
Financial assets [member]
Financial assets of the concession
Financial assets	7,084	5,303
Financial assets [member] \| Distribution concessions [member]
Financial assets of the concession
Financial assets	371	215
Financial assets [member] \| Transmission concessions [member]
Financial assets of the concession
Financial assets	547	482
Financial assets [member] \| Transmission receivable [Member]
Financial assets of the concession
Financial assets	1,928	1,805
Financial assets [member] \| Generation receivable [Member]
Financial assets of the concession
Financial assets	1,901	547
Financial assets [member] \| Concession Grant Fee [Member]
Financial assets of the concession
Financial assets	2,337	2,254
Financial assets [member] \| CVA and Other Financial Components in Tariff Adjustments [member]
Financial assets of the concession
Financial assets	R$ 369	R$ 398

The amount of current financial assets. [Refer: Financial assets]

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The amount of current financial liabilities. [Refer: Financial liabilities]

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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
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) 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 deliver 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, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are 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. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The amount of non-current financial assets. [Refer: Financial assets]

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The amount of non-current financial liabilities. [Refer: Financial liabilities]

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- Definition

Disclosure of financial assets of the concession.

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No definition available.

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Disclosure of financial liabilities of the concession.

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No definition available.

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