XML 142 R135.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Loans, Financings and Debentures - Summary of Loans Financing and Debentures (Parenthetical) (Detail) - Banco do Brasil (Cemig GT) [member] - Debt in Foreign Currency [member] - Various [member] | 12 Months Ended
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Dec. 31, 2017
Bottom of range [member] |
Disclosure of detailed information about borrowings [line items] |
Interest rate | 2.00%
Libor plus spreadrate | 0.81%
Top of range [member] |
Disclosure of detailed information about borrowings [line items] |
Interest rate | 8.00%
Libor plus spreadrate | 0.88%

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