XML 117 R110.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Concession Financial Assets and Liabilities - Summary of Auction Won Transferred to Related Specific Purpose Companies (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | R$ 2,254 | R$ 2,216
Monetary updating | 317 | 352
Amounts received | (234) | (314)
Ending Balance | 2,337 | 2,254
Cemig Geracao Tres Marias SA [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 1,283 | 1,260
Monetary updating | 172 | 192
Amounts received | (125) | (169)
Ending Balance | 1,330 | 1,283
Cemig Geracao Salto Grande SA [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 403 | 396
Monetary updating | 54 | 60
Amounts received | (40) | (53)
Ending Balance | 417 | 403
Cemig Geracao Itutinga SA [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 150 | 148
Monetary updating | 23 | 25
Amounts received | (17) | (23)
Ending Balance | 156 | 150
Cemig Geracao Camargos SA [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 112 | 110
Monetary updating | 17 | 18
Amounts received | (13) | (16)
Ending Balance | 116 | 112
Cemig Geracao Sul S.A. [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 147 | 145
Monetary updating | 23 | 26
Amounts received | (18) | (24)
Ending Balance | 152 | 147
Cemig Geracao Leste SA [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 99 | 98
Monetary updating | 17 | 19
Amounts received | (13) | (18)
Ending Balance | 103 | 99
Cemig Geracao Oeste S.A. [member] |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [Line Items] |  |
Beginning Balance | 60 | 59
Monetary updating | 11 | 12
Amounts received | (8) | (11)
Ending Balance | R$ 63 | R$ 60

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- Definition The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Subsidiaries [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2017-01-01 -Paragraph 40 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_40_a&doctype=Standard -URIDate 2017-03-09 + Details
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