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Related Party Transactions - Summary of Cemig is Provider of Surety or Guarantee of Loans, Financings and Debentures of Related Parties (Detail) R$ in Millions | 12 Months Ended
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Dec. 31, 2017 BRL (R$)
Disclosure of transactions between related parties [line items] |
Related party transaction amount | R$ 5,928
Norte Energia S.A [Member] |
Disclosure of transactions between related parties [line items] |
Related party | Norte Energia ('Nesa')
Relationship | Affiliated
Type | Surety
Objective | Financing
Expiration | 2042
Related party transaction amount | R$ 2,507
Light [member] |
Disclosure of transactions between related parties [line items] |
Related party | Light
Relationship | Jointly-controlled entity
Type | Counter-guarantee
Objective | Financing
Expiration | 2042
Related party transaction amount | R$ 684
Santo Antnio Energia S.A. [Member] |
Disclosure of transactions between related parties [line items] |
Related party | Santo Antônio Energia S.A. (Saesa)
Relationship | Jointly-controlled entity
Type | Surety
Objective | Financing
Expiration | 2034
Related party transaction amount | R$ 1,946
Santo Antnio Energia S.A. One [Member] |
Disclosure of transactions between related parties [line items] |
Related party | Santo Antônio Energia S.A. (Saesa)
Relationship | Jointly-controlled entity
Type | Surety
Objective | Debentures
Expiration | 2037
Related party transaction amount | R$ 783
Centroeste [member] |
Disclosure of transactions between related parties [line items] |
Related party | Centroeste
Relationship | Jointly-controlled entity
Type | Surety
Objective | Financing
Expiration | 2023
Related party transaction amount | R$ 8

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- Definition The description of related party transactions. [Refer: Related parties [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 24 -IssueDate 2017-01-01 -Paragraph 18 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=24&date=2017-03-01&anchor=para_18&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition Related Party Transaction Amounts Of Transaction1 + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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