XML 160 R124.htm IDEA: XBRL DOCUMENT
v3.22.1

PROPERTY, PLANT AND EQUIPMENT (Details Narrative) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Hydroelectric Generation [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Average annual depreciation rate | 3.33% | 3.14% | 3.13%

X
- References No definition available. + Details
Name: | cig_AverageAnnualDepreciationRatePropertyPlantAndEquipment
Namespace Prefix: | cig_
Data Type: | num:percentItemType
Balance Type: | na
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
- Details
Name: | ifrs-full_SegmentsAxis=cig_HydroelectricGenerationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |