Name:	cig_DisclosureOfIncomeAndSocialContributionTaxesLineItems
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The amount of effects allocated to net profit from discontinuing operations.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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IFRS adjustments for first time adoption.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The amount of income tax related to other comprehensive income.

No definition available.

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The amount of other income and social tax contribution.

No definition available.

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Reversal of deemed cost.

No definition available.

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Transfer of Assets Held For Sale.

No definition available.

Name:	cig_TransferOfAssetsHeldForSale
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The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
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-URIDate 2020-01-01

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The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2020-01-01
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-URIDate 2020-01-01

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Period Type:	instant

The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
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-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_90&doctype=Standard
-URIDate 2020-01-01

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The increase (decrease) in a deferred tax liability (asset). [Refer: Deferred tax liability (asset)]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81&doctype=Standard
-URIDate 2020-01-01