XML 119 R83.htm IDEA: XBRL DOCUMENT
v3.22.1

Schedule of operating revenues, costs and expenses (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | R$ 33,646 | R$ 25,228 | R$ 25,486
Materials, outsourced services and others expenses (revenues) | 94 | 79 | 91
Construction costs | 2,036 | 1,581 | 1,200
OPERATING COSTS AND EXPENSES | 28,237 | 21,432 | 22,474
Result of business combination | (4) | (51) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 6,951 | 4,706 | 3,210
Finance expenses | 844 | 2,445 | 3,207
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 4,699 | 3,801 | 4,570
Income tax and social contribution tax | (946) | (936) |
NET INCOME FOR THE YEAR | 3,753 | 2,865 | 2,971
Operating segments [member] | Transmission Segment [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 2,921 | 2,589 | 3,755
COST OF ENERGY AND GAS | (795) | (528) | (658)
Personnel | (149) | (170) | (164)
Employees’ and managers’ profit sharing | (14) | (16) | (24)
Post-employment obligations | (5) | (42) | (34)
Materials, outsourced services and others expenses (revenues) | (209) | (178) | (170)
Depreciation and amortization | (254) | (205) | (212)
Operating provisions and impairment | (20) | (32) | (271)
Construction costs |  |  |
Total cost of operation | (651) | (643) | (875)
OPERATING COSTS AND EXPENSES | (1,446) | (1,171) | (1,533)
Periodic tariff review, net |  |  | 23
Dividends declared by investee classified as held for sale | 1,032 |  |
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net | 54 | 11 |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 2,561 | 1,429 | 2,245
Finance expenses | (758) | (322) | 113
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 1,803 | 1,107 | 2,358
Income tax and social contribution tax | (409) | (308) | (641)
NET INCOME FOR THE YEAR | 1,394 | 799 | 1,717
Equity holders of the parent | 1,394 | 799 |
Non-controlling interests |  |  |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  | 1,717
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  | 1,717
Net income from continuing operations |  |  |
Operating segments [member] | Tranding Segment [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 1,094 | 778 | 934
COST OF ENERGY AND GAS |  |  |
Personnel | (115) | (102) | (113)
Employees’ and managers’ profit sharing | (14) | (14) | (27)
Post-employment obligations | 3 | (38) | (38)
Materials, outsourced services and others expenses (revenues) | (94) | (65) | (67)
Depreciation and amortization | (3) | (5) | (3)
Operating provisions and impairment | (12) | 7 | (72)
Construction costs | (184) | (147) | (221)
Total cost of operation | (419) | (364) | (541)
OPERATING COSTS AND EXPENSES | (419) | (364) | (541)
Periodic tariff review, net | 215 | 502 | 4
Dividends declared by investee classified as held for sale |  |  | 73
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net |  |  |
Result of business combination | 4 |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 894 | 967 | 470
Finance expenses | (395) | (152) | 98
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 499 | 815 | 568
Income tax and social contribution tax | (78) | (222) | (112)
NET INCOME FOR THE YEAR | 421 | 593 | 456
Equity holders of the parent | 421 | 593 |
Non-controlling interests |  |  |
Fair value of business combination |  | 51 |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  | 456
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  | 456
Net income from continuing operations |  |  |
Operating segments [member] | Distribution Segment [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 6,430 | 5,382 | 4,595
COST OF ENERGY AND GAS | (5,735) | (5,027) | (4,801)
Personnel | (20) | (16) | (19)
Employees’ and managers’ profit sharing | (3) | (2) | (5)
Post-employment obligations | (1) | (6) | (7)
Materials, outsourced services and others expenses (revenues) | (14) | (11) | (14)
Depreciation and amortization | (1) | (1) |
Operating provisions and impairment | (14) | (1) | (10)
Construction costs |  |  |
Total cost of operation | (53) | (37) | (55)
OPERATING COSTS AND EXPENSES | (5,788) | (5,064) | (4,856)
Periodic tariff review, net |  |  |
Dividends declared by investee classified as held for sale |  |  |
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net |  |  |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 642 | 318 | (261)
Finance expenses | 15 | 21 | 10
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 657 | 339 | (251)
Income tax and social contribution tax | (224) | (81) | 150
NET INCOME FOR THE YEAR | 433 | 258 | (101)
Equity holders of the parent | 433 | 258 |
Non-controlling interests |  |  |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  | (101)
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  | (101)
Net income from continuing operations |  |  |
Operating segments [member] | Other Segments [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 22,345 | 16,512 | 15,919
COST OF ENERGY AND GAS | (14,853) | (9,960) | (8,975)
Personnel | (847) | (886) | (869)
Employees’ and managers’ profit sharing | (94) | (93) | (183)
Post-employment obligations | 19 | (297) | (277)
Materials, outsourced services and others expenses (revenues) | (1,524) | (1,327) | (1,375)
Depreciation and amortization | (683) | (668) | (652)
Operating provisions and impairment | (198) | (274) | (1,103)
Construction costs | (1,802) | (1,384) | (936)
Total cost of operation | (5,129) | (4,929) | (5,395)
OPERATING COSTS AND EXPENSES | (19,982) | (14,889) | (14,370)
Periodic tariff review, net |  |  |
Dividends declared by investee classified as held for sale |  |  |
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net |  |  |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 2,363 | 1,623 | 1,549
Finance expenses | (7) | 22 | 902
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 2,356 | 1,645 | 2,450
Income tax and social contribution tax | (655) | (430) | (806)
NET INCOME FOR THE YEAR | 1,701 | 1,215 | 1,644
Equity holders of the parent | 1,701 | 1,215 |
Non-controlling interests |  |  |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  | 1,644
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  | 1,644
Net income from continuing operations |  |  |
Operating segments [member] | Investees Segments [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 2,858 | 1,673 | 2,054
COST OF ENERGY AND GAS | (2,011) | (1,083) | (1,436)
Personnel | (109) | (102) | (107)
Employees’ and managers’ profit sharing | (9) | (17) | (24)
Post-employment obligations | (32) | (55) | (52)
Materials, outsourced services and others expenses (revenues) | (165) | (110) | (247)
Depreciation and amortization | (108) | (110) | (91)
Operating provisions and impairment | (120) | (123) | (945)
Construction costs | (50) | (50) | (43)
Total cost of operation | (593) | (567) | (1,509)
OPERATING COSTS AND EXPENSES | (2,604) | (1,650) | (2,945)
Periodic tariff review, net |  |  | 98
Dividends declared by investee classified as held for sale |  |  |
Gains arising from the sale of non-current asset held for sale | 109 |  |
Equity in earnings of unconsolidated investees, net | 128 | 346 |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 491 | 369 | (793)
Finance expenses | (1,107) | (474) | 237
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | (616) | (105) | (555)
Income tax and social contribution tax | 420 | 105 | (191)
NET INCOME FOR THE YEAR | (196) |  | (522)
Equity holders of the parent | (198) | (1) |
Non-controlling interests | 2 | 1 |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  | 224
Net income from continuing operations |  |  | (747)
Net income from discontinued operations |  |  | 224
Net income for the year attributed to equity holders of the parent |  |  | (523)
Net income from continuing operations |  |  | 1
Operating segments [member] | Total Segments [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 35,648 | 26,934 | 27,257
COST OF ENERGY AND GAS | (23,394) | (16,598) | (15,870)
Personnel | (1,240) | (1,276) | (1,272)
Employees’ and managers’ profit sharing | (134) | (142) | (263)
Post-employment obligations | (16) | (438) | (408)
Materials, outsourced services and others expenses (revenues) | (2,006) | (1,691) | (1,873)
Depreciation and amortization | (1,049) | (989) | (958)
Operating provisions and impairment | (364) | (423) | (2,401)
Construction costs | (2,036) | (1,581) | (1,200)
Total cost of operation | (6,845) | (6,540) | (8,375)
OPERATING COSTS AND EXPENSES | (30,239) | (23,138) | (24,245)
Periodic tariff review, net | 215 | 502 | 125
Dividends declared by investee classified as held for sale | 1,032 |  | 73
Gains arising from the sale of non-current asset held for sale | 109 |  |
Equity in earnings of unconsolidated investees, net | 182 | 357 |
Result of business combination | 4 |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 6,951 | 4,706 | 3,210
Finance expenses | (2,252) | (905) | 1,360
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 4,699 | 3,801 | 4,570
Income tax and social contribution tax | (946) | (936) | (1,600)
NET INCOME FOR THE YEAR | 3,753 | 2,865 | 3,194
Equity holders of the parent | 3,751 | 2,864 |
Non-controlling interests | 2 | 1 |
Fair value of business combination |  | 51 |
Net income after tax from discontinued operations |  |  | 224
Net income from continuing operations |  |  | 2,969
Net income from discontinued operations |  |  | 224
Net income for the year attributed to equity holders of the parent |  |  | 3,193
Net income from continuing operations |  |  | 1
Operating segments [member] | Intersegment Transactions Segments [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | (1,575) | (1,324) | (1,409)
COST OF ENERGY AND GAS | 1,575 | 1,324 | 1,409
Personnel |  |  |
Employees’ and managers’ profit sharing |  |  |
Post-employment obligations |  |  |
Materials, outsourced services and others expenses (revenues) |  |  |
Depreciation and amortization |  |  |
Operating provisions and impairment |  |  |
Construction costs |  |  |
Total cost of operation |  |  |
OPERATING COSTS AND EXPENSES | 1,575 | 1,324 | 1,409
Periodic tariff review, net |  |  |
Dividends declared by investee classified as held for sale |  |  |
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net |  |  |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |
Finance expenses |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |
Income tax and social contribution tax |  |  |
NET INCOME FOR THE YEAR |  |  |
Equity holders of the parent |  |  |
Non-controlling interests |  |  |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  |
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  |
Net income from continuing operations |  |  |
Operating segments [member] | Reconciliation Segments [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | (427) | (382) | (362)
COST OF ENERGY AND GAS | 370 | 332 | 313
Personnel |  |  |
Employees’ and managers’ profit sharing |  |  |
Post-employment obligations |  |  |
Materials, outsourced services and others expenses (revenues) | 57 | 50 | 49
Depreciation and amortization |  |  |
Operating provisions and impairment |  |  |
Construction costs |  |  |
Total cost of operation | 57 | 50 | 49
OPERATING COSTS AND EXPENSES | 427 | 382 | 362
Periodic tariff review, net |  |  |
Dividends declared by investee classified as held for sale |  |  |
Gains arising from the sale of non-current asset held for sale |  |  |
Equity in earnings of unconsolidated investees, net |  |  |
Result of business combination |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |
Finance expenses |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |
Income tax and social contribution tax |  |  |
NET INCOME FOR THE YEAR |  |  |
Equity holders of the parent |  |  |
Non-controlling interests |  |  |
Fair value of business combination |  |  |
Net income after tax from discontinued operations |  |  |
Net income from continuing operations |  |  |
Net income from discontinued operations |  |  |
Net income for the year attributed to equity holders of the parent |  |  |
Net income from continuing operations |  |  |
Operating segments [member] | All other segments [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
NET REVENUE | 33,646 | 25,228 | 25,486
COST OF ENERGY AND GAS | (21,449) | (14,942) | (14,148)
Personnel | (1,240) | (1,276) | (1,272)
Employees’ and managers’ profit sharing | (134) | (142) | (263)
Post-employment obligations | (16) | (438) | (408)
Materials, outsourced services and others expenses (revenues) | (1,949) | (1,641) | (1,824)
Depreciation and amortization | (1,049) | (989) | (958)
Operating provisions and impairment | (364) | (423) | (2,401)
Construction costs | (2,036) | (1,581) | (1,200)
Total cost of operation | (6,788) | (6,490) | (8,326)
OPERATING COSTS AND EXPENSES | (28,237) | (21,432) | (22,474)
Periodic tariff review, net | 215 | 502 | 125
Dividends declared by investee classified as held for sale | 1,032 |  | 73
Gains arising from the sale of non-current asset held for sale | 109 |  |
Equity in earnings of unconsolidated investees, net | 182 | 357 |
Result of business combination | 4 |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | 6,951 | 4,706 | 3,210
Finance expenses | (2,252) | (905) | 1,360
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | 4,699 | 3,801 | 4,570
Income tax and social contribution tax | (946) | (936) | (1,600)
NET INCOME FOR THE YEAR | 3,753 | 2,865 | 3,194
Equity holders of the parent | 3,751 | 2,864 |
Non-controlling interests | R$ 2 | 1 |
Fair value of business combination |  | R$ 51 |
Net income after tax from discontinued operations |  |  | 224
Net income from continuing operations |  |  | 2,969
Net income from discontinued operations |  |  | 224
Net income for the year attributed to equity holders of the parent |  |  | 3,193
Net income from continuing operations |  |  | R$ 1

X
- References No definition available. + Details
Name: | cig_AdjustmentsForDepreciationAndAmortisationExpenseOne
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_AdjustmentsForProvisionsOne
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_ComprehensiveIncomeAttributableToOwnersOfParentOne
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_ConstructionContractsCosts
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_CostOfEnergyGasAndChargesForUseOfNationalGrid
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_CostsAndExpenses1
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_CostsChargedToOperatingProfit
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_EquityInEarningsOfUnconsolidatedInvesteesNet
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_ExpenseFromSharebasedPaymentTransactionsWithEmployeesOne
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_FairValueOfBusinessCombination
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_GainsArisingFromSaleOfNoncurrentAssetHeldForSale1
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_IfrsStatementLineItems
Namespace Prefix: | cig_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_IncomeBeforeFinancialIncomeExpensesAndTaxes
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_NetIncomeAfterTaxFromDiscontinuedOperations
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_NetIncomeForYearAttributedToEquityHoldersOfParent
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_NetIncomeFromContinuingOperations
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_NetIncomeFromContinuingOperations1
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_NetIncomeFromDiscontinuedOperations
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_PeriodicTariffReviewNet
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_PersonnelExpensesOne
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_PostEmploymentObligations
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_RenegotiationOfHydrologicalRiskLaw1405220Net1
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_ResultOfBusinessCombination
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of income associated with interest and other financing activities of the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_85&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_FinanceIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2021-01-01 -Paragraph 35 -Subparagraph b -Clause viii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=26&code=ifrs-tx-2021-en-r&anchor=para_35_b_viii&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 23 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23_h&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2021-01-01 -Paragraph 79 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_79&doctype=Standard -URIDate 2021-03-24 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2021-01-01 -Paragraph 81 -Subparagraph c -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_81_c_i&doctype=Standard -URIDate 2021-03-24 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 82 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_82_d&doctype=Standard -URIDate 2021-03-24 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2021-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2021-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2021-03-24 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph B13 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B13_g&doctype=Appendix&subtype=B -URIDate 2021-03-24 + Details
Name: | ifrs-full_IncomeTaxExpenseContinuingOperations
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The profit (loss) from continuing and discontinued operations attributable to non-controlling interests. [Refer: Profit (loss); Non-controlling interests] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph 12 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_12_e&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 81B -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_81B_a_i&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_ProfitLossAttributableToNoncontrollingInterests
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The profit (loss) before tax expense or income. [Refer: Profit (loss)] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 28 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_b&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_103&doctype=Standard -URIDate 2021-03-24 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_102&doctype=Standard -URIDate 2021-03-24 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 5 -IssueDate 2021-01-01 -Paragraph 33 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=5&code=ifrs-tx-2021-en-r&anchor=para_33_b_i&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_ProfitLossBeforeTax
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The profit (loss) from continuing operations. [Refer: Continuing operations [member]; Profit (loss)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 28 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_b&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph B12 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B12_b_vi&doctype=Appendix&subtype=B -URIDate 2021-03-24 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 81A -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_81A_a&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_ProfitLossFromContinuingOperations
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of raw materials and consumables used in the production process or in the rendering of services. [Refer: Current raw materials] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_102&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 99 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_99&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_RawMaterialsAndConsumablesUsed
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 28 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_a&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 23 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23_a&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 32 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_32&doctype=Standard -URIDate 2021-03-24 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 33 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_33_a&doctype=Standard -URIDate 2021-03-24 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 34 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_34&doctype=Standard -URIDate 2021-03-24 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 82 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_82_a&doctype=Standard -URIDate 2021-03-24 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_103&doctype=Standard -URIDate 2021-03-24 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_102&doctype=Standard -URIDate 2021-03-24 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 5 -IssueDate 2021-01-01 -Paragraph 33 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=5&code=ifrs-tx-2021-en-r&anchor=para_33_b_i&doctype=Standard -URIDate 2021-03-24 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph B12 -Subparagraph b -Clause v -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B12_b_v&doctype=Appendix&subtype=B -URIDate 2021-03-24 Reference 11: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph B10 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B10_b&doctype=Appendix&subtype=B -URIDate 2021-03-24 + Details
Name: | ifrs-full_Revenue
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ifrs-full_SegmentConsolidationItemsAxis=ifrs-full_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_TransmissionSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_TrandingSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_DistributionSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_OtherSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_InvesteesSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_TotalSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_IntersegmentTransactionsSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cig_ReconciliationSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=ifrs-full_AllOtherSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |