XML 199 R192.htm IDEA: XBRL DOCUMENT v3.8.0.1

Related Party Transactions - Summary of Financial Investments in Securities of Related Parties, in the Investment Fund (Detail) - Related parties [member] - Investment	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Number Of Investments	21	12
ETAU [member]
Investment [Line Items]
Type	Debentures	Debentures
Annual contractual conditions	108.00% of CDI	108.00% of CDI
Maturity	Dec. 01, 2019	Dec. 01, 2019
Number Of Investments	7	8
Light [member]
Investment [Line Items]
Type	Promissory Note
Annual contractual conditions	CDI + 3.50%
Maturity	Jan. 22, 2019
Number Of Investments	14
Axxiom [member]
Investment [Line Items]
Type		Debentures
Annual contractual conditions		109.00% of CDI Rate
Maturity		Jan. 29, 2017
Number Of Investments		4
Cemig [member]
Investment [Line Items]
Number Of Investments	1	2
Cemig [member] | ETAU [member]
Investment [Line Items]
Number Of Investments		1
Cemig [member] | Light [member]
Investment [Line Items]
Number Of Investments	1
Cemig [member] | Axxiom [member]
Investment [Line Items]
Number Of Investments		1
Cemig GT [member]
Investment [Line Items]
Number Of Investments	8	3
Cemig GT [member] | ETAU [member]
Investment [Line Items]
Number Of Investments	3	2
Cemig GT [member] | Light [member]
Investment [Line Items]
Number Of Investments	5
Cemig GT [member] | Axxiom [member]
Investment [Line Items]
Number Of Investments		1
Cemig D [member]
Investment [Line Items]
Number Of Investments	6	4
Cemig D [member] | ETAU [member]
Investment [Line Items]
Number Of Investments	2	3
Cemig D [member] | Light [member]
Investment [Line Items]
Number Of Investments	4
Cemig D [member] | Axxiom [member]
Investment [Line Items]
Number Of Investments		1
Other Subsidiaries [Member]
Investment [Line Items]
Number Of Investments	6	3
Other Subsidiaries [Member] | ETAU [member]
Investment [Line Items]
Number Of Investments	2	2
Other Subsidiaries [Member] | Light [member]
Investment [Line Items]
Number Of Investments	4
Other Subsidiaries [Member] | Axxiom [member]
Investment [Line Items]
Number Of Investments		1

X

- Definition

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

+ Details

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- Definition

The maturity date of the investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

+ Details

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- Definition

Description of percentage of investments in related parties.

+ References

No definition available.

+ Details

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- Definition

Description of type of securities.

+ References

No definition available.

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- Definition

Number of investment units.

+ References

No definition available.

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