XML 220 R213.htm IDEA: XBRL DOCUMENT v3.8.0.1

Insurance - Summary of Amounts Arising From Insurance Contracts (Parenthetical) (Detail) - 12 months ended Dec. 31, 2017 R$ in Millions, $ in Millions	BRL (R$)	USD ($)
Disclosure of types of insurance contracts [line items]
Expense arising from insurance	R$ 0	$ 0
Cemig Geracao e Transmissao [member]
Disclosure of types of insurance contracts [line items]
Maximum indemnity limit	231
Cemig Distribution [member]
Disclosure of types of insurance contracts [line items]
Maximum indemnity limit	R$ 214

X

- 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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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of expense arising from insurance contracts. [Refer: Types of insurance contracts [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 4
-IssueDate 2017-01-01
-Paragraph 37
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=4&date=2017-03-01&anchor=para_37_b&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Maximum indemnity limit of insurance contract.

+ References

No definition available.

+ Details

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Namespace Prefix:	xcmig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type: