Schedule of detailed information about concession contract assets (Details) - BRL (R$) R$ in Millions	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Contract assets	R$ 6,380	R$ 4,980
Current contract assets	600	737
Non-current contract assets	5,780	4,243
Restated 1 [Member]
IfrsStatementLineItems [Line Items]
Current contract assets	600	737
Non-current contract assets	5,780	4,243
Distribution Infrastructure Assets Under Construction [Member]
IfrsStatementLineItems [Line Items]
Contract assets	1,927	1,142
Gas Infrastructure Assets Under Construction [Member]
IfrsStatementLineItems [Line Items]
Contract assets	95	94
National Grid [Member]
IfrsStatementLineItems [Line Items]
Contract assets	2,011	1,896
Transmission Indemnity Assets Incorporated Into The Assets Remuneration Base [Member]
IfrsStatementLineItems [Line Items]
Contract assets	R$ 2,347	R$ 1,848

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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 2021-01-01
-Paragraph 105
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-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2021-01-01
-Paragraph 116
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2021-en-r&anchor=para_116_a&doctype=Standard
-URIDate 2021-03-24

+ Details

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- Definition

The amount of current contract assets. [Refer: Contract assets]

+ References

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- Definition

The amount of non-current contract assets. [Refer: Contract assets]

+ References

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