Name:	cig_DeficitRate
Namespace Prefix:	cig_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Represent information about the description of monthly amortizations.

No definition available.

Name:	cig_DescriptionOfMonthlyAmortizations
Namespace Prefix:	cig_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	cig_IfrsStatementLineItems
Namespace Prefix:	cig_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The information represents the inflation index rate.

No definition available.

Name:	cig_InflationIndexRate
Namespace Prefix:	cig_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The information represents the interest rate on benefit plan.

No definition available.

Name:	cig_InterestRateOnBenefitPlan
Namespace Prefix:	cig_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The present value of the expected payments by a retirement benefit plan to existing and past employees, attributable to the service already rendered.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 26
-IssueDate 2022-03-24
-Paragraph 35
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2022-en-r&anchor=para_35_d&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_ActuarialPresentValueOfPromisedRetirementBenefits
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of benefits paid or payable for retirement benefit plans.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 26
-IssueDate 2022-03-24
-Paragraph 35
-Subparagraph b
-Clause v
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2022-en-r&anchor=para_35_b_v&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_BenefitsPaidOrPayable
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 7
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_7&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_BorrowingsInterestRate
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The amount of deposit liabilities from customers held by the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_55&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_DepositsFromCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Description of contractual payment terms of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Includes, but is not limited to, whether mortgage loan is payable at level or varying amount to maturity, balloon payment requirement at maturity, and prepayment penalty.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column D
-Subsection 29