FINANCIAL INSTRUMENTS (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2023	Dec. 31, 2022
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	R$ 19,546,276	R$ 15,578,870
Total current financial assets	21,078,889	16,773,361
Total current financial assets at fair value through profit or loss	1,532,613	1,194,491
Total non-current financial assets at amortised cost	2,976,607	2,581,910
Total non-current financial assets	3,055,344	2,676,610
Total non-current financial assets at fair value through profit or loss	78,737	94,700
Total financial assets at fair value through profit or loss	1,611,350	1,289,191
Total financial assets at amortised cost	22,522,883	18,160,780
Total financial assets	24,134,233	19,449,971
[custom:FairValueThroughOtherComprehensiveIncome-0]	672,280
Financial liabilities at fair value through profit or loss	324,215	486,407
Financial liabilities at amortised cost	58,342,488	55,175,650
Financial liabilities	59,338,983	55,662,057
Dividends And Interest On Equity [Member]
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	185,178	77,377
Total current financial assets	185,178	77,377
Cash And Cash Equivalant [Member]
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	16,046,218	11,991,356
Total current financial assets	16,046,218	11,991,356
Short Term Investment [Member]
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	39,800	271,590
Total current financial assets	1,533,004	1,184,895
Total current financial assets at fair value through profit or loss	1,493,204	1,456,485
Trade receivables [member]
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	3,269,764	3,233,164
Total current financial assets	3,269,764	3,233,164
Derivatives [member]
IfrsStatementLineItems [Line Items]
Total current financial assets	32,211
Total current financial assets at fair value through profit or loss	32,211
Current financial liabilities at fair value through profit or loss	263,747	416,935
Non-current financial liabilities at fair value through profit or loss	60,468	69,472
Trading securities [member]
IfrsStatementLineItems [Line Items]
Total current financial assets	7,198	9,596
Total current financial assets at fair value through profit or loss	7,198	9,596
Related parties [member]
IfrsStatementLineItems [Line Items]
Total current financial assets at amortised cost	5,316	5,383
Total current financial assets	5,316	5,383
Total non-current financial assets at amortised cost	1,659,412	1,384,773
Total non-current financial assets	1,659,412	1,384,773
Investment property [member]
IfrsStatementLineItems [Line Items]
Total non-current financial assets at amortised cost	251,299	156,185
Total non-current financial assets	251,299	156,185
Total non-current financial assets at fair value through profit or loss	78,737	94,700
Other Trade Receivables [Member]
IfrsStatementLineItems [Line Items]
Total non-current financial assets at amortised cost	10,406	8,059
Total non-current financial assets	10,406	8,059
Eletrobras Compulsory Loan [Member]
IfrsStatementLineItems [Line Items]
Total non-current financial assets at amortised cost	62,913	58,030
Total non-current financial assets	62,913	58,030
Receivables By Indemnity [Member]
IfrsStatementLineItems [Line Items]
Total non-current financial assets at amortised cost	992,577	974,863
Total non-current financial assets	992,577	974,863
Investment Property 1 [Member]
IfrsStatementLineItems [Line Items]
Total non-current financial assets	78,737	94,700
Total non-current financial assets at fair value through profit or loss	78,737	94,700
Borrowings And Financing [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	7,701,796	5,269,952
Current financial liabilities	7,701,796	5,269,952
Non-current financial liabilities at amortised cost	37,772,116	36,170,996
Non-current financial liabilities	37,772,116	36,170,996
Leases [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	137,638	177,010
Current financial liabilities	137,638	177,010
Non-current financial liabilities at amortised cost	596,123	516,836
Non-current financial liabilities	596,123	516,836
Trade Payables [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	7,739,520	6,596,915
Current financial liabilities	7,739,520	6,596,915
Non-current financial liabilities at amortised cost	31,060	46,269
Non-current financial liabilities	31,060	46,269
Trade Payables Drawee Risk [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	4,209,434	5,709,069
Current financial liabilities	4,209,434	5,709,069
Dividends And Interest On Capital [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	80,624	611,307
Current financial liabilities	80,624	611,307
Derivative Financial Instruments [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities	936,027	416,935
[custom:FairValueThroughOtherComprehensiveIncomeLiabilitiesCurrent-0]	672,280
Current financial liabilities at fair value through profit or loss	263,747	416,935
Non-current financial liabilities	60,468	69,472
Non-current financial liabilities at fair value through profit or loss	60,468	69,472
Liabilities Current [Member]
IfrsStatementLineItems [Line Items]
Current financial liabilities at amortised cost	19,869,012	18,364,253
Current financial liabilities	20,805,039	18,781,188
[custom:FairValueThroughOtherComprehensiveIncomeLiabilitiesCurrent-0]	672,280
Current financial liabilities at fair value through profit or loss	263,747	416,935
Concessions Payable [Member]
IfrsStatementLineItems [Line Items]
Non-current financial liabilities at amortised cost	74,177	77,296
Non-current financial liabilities	74,177	77,296
Liabilities Non Current [Member]
IfrsStatementLineItems [Line Items]
Non-current financial liabilities at amortised cost	38,473,476	36,811,397
Non-current financial liabilities	38,533,944	36,880,869
Non-current financial liabilities at fair value through profit or loss	R$ 60,468	R$ 69,472

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

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The amount of current financial assets measured at amortised cost. [Refer: Financial assets at amortised cost]

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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]

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The amount of financial assets at amortised cost. The amortised cost is the amount at which financial assets are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount, and adjusted for any impairment. [Refer: Financial assets]

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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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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 financial liabilities at amortised cost. The amortised cost is the amount at which financial liabilities are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount. [Refer: Financial liabilities]

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The amount of financial liabilities that meet either of the following conditions: (a) they meet the definition of held for trading; or (b) upon initial recognition they are designated by the entity as at fair value through profit or loss. An entity may use this designation only when permitted by paragraph 4.3.5 of IFRS 9 (embedded derivatives) or when doing so results in more relevant information, because either: (a) it eliminates or significantly reduces a measurement or recognition inconsistency (sometimes referred to as ‘an accounting mismatch’) that would otherwise arise from measuring assets or liabilities or recognising the gains and losses on them on different bases; or (b) a group of financial liabilities or financial assets and financial liabilities is managed and its performance is evaluated on a fair value basis, in accordance with a documented risk management or investment strategy, and information about the group is provided internally on that basis to the entity’s key management personnel (as defined in IAS 24). [Refer: At fair value [member]; Key management personnel of entity or parent [member]; Derivatives [member]; Financial assets; Financial liabilities]

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

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The amount of non-current financial assets measured at amortised cost. [Refer: Financial assets at amortised cost]

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The amount of non-current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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

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The amount of non-current financial liabilities measured at amortised cost. [Refer: Financial liabilities at amortised cost]

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