XML 122 R115.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Investments - Allocation of Acquisition Price of Jointly-Controlled Subsidiaries, A Valuation was Made of Intangible Assets Relating to Right to Operate Regulated Activity (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | R$ 801 | R$ 861 | R$ 906
Addition |  | 99 |
Amortization | (54) | (50) | (45)
Written off | (129) | (109) |
Ending balance | 618 | 801 | 861
Taesa [member] |  |  |
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | 288 | 415 | 433
Amortization | (13) | (18) | (18)
Written off | (86) | (109) |
Ending balance | 189 | 288 | 415
Light [member] |  |  |
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | 209 | 231 | 253
Amortization | (23) | (22) | (22)
Ending balance | 186 | 209 | 231
Gasmig [member] |  |  |
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | 207 | 215 | 220
Amortization | (7) | (8) | (5)
Ending balance | 200 | 207 | R$ 215
Lepsa [member] |  |  |
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | 49 |  |
Addition |  | 50 |
Amortization | (6) | (1) |
Written off | (43) |  |
Ending balance |  | 49 |
RME [member] |  |  |
Disclosure of detailed information about investment property [line items] |  |  |
Beginning balance | 48 |  |
Addition |  | 49 |
Amortization | (5) | (1) |
Ending balance | R$ 43 | R$ 48 |

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- Definition The amount of additions to investment property other than those acquired through business combinations. [Refer: Business combinations [member]; Investment property] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 76 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76_a&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d_i&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 Expiry date 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee under a finance lease) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business. Effective 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 76 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_79_d&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_b&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Amortization investment property. + References No definition available. + Details
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- Definition Written off of investments. + 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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- Details
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