Concession Financial and Sector Assets and Liabilities - Schedule of Changes in Concession Financial Assets (Details) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
IfrsStatementLineItems [Line Items]
Beginning balance	R$ 6,540
Amounts received	(343)	R$ (331)	R$ (309)
Classification as held for sale	(36)
Ending balance	8,072	6,540
Assets related to infrastructure [member]
IfrsStatementLineItems [Line Items]
Beginning balance	5,735
Ending balance	6,776	5,735
Infrastructure [Member]
IfrsStatementLineItems [Line Items]
Beginning balance	5,735	5,049	4,326
Transfers from contract assets	782	363	670
Transfers from (to) intangible assets			(22)
Monetary updating	641	654	556
Fair Value Adjustments			(172)
Disposals	(2)		(1)
Amounts received	(343)	(331)
Classification as held for sale	(37)
Ending balance	6,776	5,735	5,049
Energy Distribution [Member]
IfrsStatementLineItems [Line Items]
Classification as held for sale
Energy Distribution [Member] \| Infrastructure [Member]
IfrsStatementLineItems [Line Items]
Beginning balance	1,881	1,370	684
Transfers from contract assets	731	363	670
Transfers from (to) intangible assets			(22)
Monetary updating	104	148	39
Fair Value Adjustments
Disposals	(2)		(1)
Amounts received
Ending balance	2,714	1,881	1,370
Generation [member] \| Infrastructure [Member]
IfrsStatementLineItems [Line Items]
Beginning balance	3,816	3,642	3,608
Transfers from contract assets
Transfers from (to) intangible assets
Monetary updating	534	505	514
Fair Value Adjustments			(172)
Disposals
Amounts received	(343)	(331)	(308)
Classification as held for sale	(37)
Ending balance	3,970	3,816	3,642
Gas Distribution [Member]
IfrsStatementLineItems [Line Items]
Classification as held for sale
Gas Distribution [Member] \| Infrastructure [Member]
IfrsStatementLineItems [Line Items]
Beginning balance	38	37	34
Transfers from contract assets	51
Transfers from (to) intangible assets
Monetary updating	3	1	3
Fair Value Adjustments
Disposals
Amounts received
Ending balance	R$ 92	R$ 38	R$ 37

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Ifrs Statement Line Items

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Transfers between property plant and equipment and concession contract assets.

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Transfers between property plant and equipment financial assets and intangible assets

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Adjustments for fair value losses (gains) to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)]

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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: Classes of financial instruments [domain]; Financial liabilities]

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