Concession Financial and Sector Assets and Liabilities - Summary of Financial Assets and Liabilities of Concession and Sector (Detail) - BRL (R$) R$ in Millions	Dec. 31, 2018	Dec. 31, 2017
Financial assets of the concession
Financial assets	R$ 16,279	R$ 16,866
Current assets	1,071	848
Non-current assets	4,927	6,605
Financial liabilities of the concession
Current liabilities		415
Amounts payable from Parcel A (CVA) and Other Financial Components [member]
Financial liabilities of the concession
Current liabilities		415
Financial assets [member]
Financial assets of the concession
Financial assets	4,917	7,084
Financial assets [member] \| Amounts payable from Parcel A (CVA) and Other Financial Components [member]
Financial assets of the concession
Financial assets	1,081	369
Financial assets [member] \| Distribution concessions [member]
Financial assets of the concession
Financial assets	396	371
Financial assets [member] \| Indemnifiable receivable Transmission [member]
Financial assets of the concession
Financial assets	1,296	1,928
Financial assets [member] \| Transmission concessions [member]
Financial assets of the concession
Financial assets		547
Financial assets [member] \| Indemnifiable receivable Generation [member]
Financial assets of the concession
Financial assets	816	1,901
Financial assets [member] \| Concession grant fee Generation concessions [member]
Financial assets of the concession
Financial assets	2,409	2,337
Concession sector assets [member]
Financial assets of the concession
Financial assets	R$ 5,998	R$ 7,453

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 4: http://www.xbrl.org/2003/role/disclosureRef
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The amount of non-current financial assets. [Refer: Financial assets]

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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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