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30. RELATED PARTY TRANSACTIONS (Details 2) R$ in Millions | 12 Months Ended
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Dec. 31, 2020 BRL (R$)
Disclosure of transactions between related parties [line items] |  |
Related party transaction amount | R$ 4,820 |
Norte energia s.a. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Related party | Norte Energia (NESA) | [1]
Relationship | Affiliated | [1]
Type | Surety | [1]
Objective | Financing | [1]
Related party transaction amount | R$ 2,601 | [1]
Maturity | 2042 | [1]
Light [member] |  |
Disclosure of transactions between related parties [line items] |  |
Related party | Light |
Relationship | Affiliated |
Type | Counter-guarantee |
Objective | Financing |
Related party transaction amount | R$ 684 |
Maturity | 2042 |
Santo Antnio Energia S.A. [member] |  |
Disclosure of transactions between related parties [line items] |  |
Related party | Santo Antônio Energia (SAESA) | [2]
Relationship | Jointly-controlled | [2]
Type | Surety | [2]
Objective | Debentures | [2]
Related party transaction amount | R$ 445 | [2]
Maturity | 2037 | [2]
Santo Antnio Energia S.A. One [member] |  |
Disclosure of transactions between related parties [line items] |  |
Related party | Santo Antônio Energia (SAESA) |
Relationship | Jointly-controlled |
Type | Guarantee |
Objective | Financing |
Related party transaction amount | R$ 1,023 |
Maturity | 2034 |
Norte Energia S.A one [member] |  |
Disclosure of transactions between related parties [line items] |  |
Related party | Norte Energia (NESA) |
Relationship | Affiliated |
Type | Surety |
Objective | Debentures |
Related party transaction amount | R$ 67 |
Maturity | 2030 |
[1] | Related to execution of guarantees of the Norte Energia financing.
[2] | Corporate guarantee given by Cemig to Saesa.

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