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3. PRINCIPLES OF CONSOLIDATION (Details Narrative) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Light [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 49.99%
Light [Member] | Top of Range [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 49.99%
Light [Member] | Bottom Of Range [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly | 22.58% |
Lightger [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 74.49%
Guanhaes [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 74.49%
UHE Itaocara [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 49.00%
Cemig Telecom [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 25.49%
Axxion [member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 25.49%
Axxion [Member] |  |
Disclosure of subsidiaries [line items] |  |
Percentage of ownership interest in entities wholly owned directly or indirectly |  | 49.00%

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- Details
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