XML 222 R186.htm IDEA: XBRL DOCUMENT
v3.22.1

Schedule of changes in value of options (Details) - Put option - SAAG [member] - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018
IfrsStatementLineItems [Line Items] |  |  |
Balance | R$ 536 | R$ 483 |
Adjustment to fair value | 100 | 53 | R$ 64
Balance | R$ 636 | R$ 536 | R$ 419

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- Definition Adjustment to fair value of options. + References No definition available. + Details
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Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- References No definition available. + Details
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Period Type: | duration

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- Definition The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_55&doctype=Standard -URIDate 2021-03-24 + Details
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Namespace Prefix: | ifrs-full_
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Balance Type: | credit
Period Type: | instant

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |