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33. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details Narrative) R$ / shares in Units, R$ in Millions |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
May 07, 2019 | Jul. 31, 2018 BRL (R$) R$ / shares | Dec. 31, 2019 BRL (R$) Number R$ / shares | Dec. 31, 2018 BRL (R$)
Disclosure of detailed information about financial instruments [line items] |  |  |  |
Description of annual rates loans and debentures |  |  | IPCA + 4.70% to 8.07% and CDI + 0.38% to 2.24% |
Exercise price of financial remuneration percentage |  |  | 133.37% |
Liability |  |  | R$ 483 | R$ 419
Risk-free interest rate |  |  | 0.81% | 3.19%
Volatility |  |  | 10.00% | 70.00%
Put option, price |  |  | R$ 492 | R$ 525
Exercise price of put option as number of times adjusted net income | Number |  |  | 15 |
Exercise price of call option as number of times adjusted net income | Number |  |  | 17 |
Option vesting date |  |  | Jan. 01, 2021 |
Non cash positive (negative) adjustment from derivative transaction |  |  | R$ 998 | 893
Swap operation floor rate | R$ / shares |  | R$ 3.85 | R$ 3.25 |
Swap ceiling rate |  | R$ 5 | R$ 5 |
FX Variation Interest rate |  | 9.25% | 9.25% |
Value of principal contracted |  | R$ 5 | R$ 1 |
Cemig's obligation |  | 125.52% of the CDI rate | 150.49% of the CDI |
Financial assets, fair value |  |  | R$ 16,098 | 16,183
Maturity | April 15, 2022 to April 15, 2025 |  |  |
Derivative hedge instrument, Liabilities |  |  | 18,764 | (18,120)
Net assets (liabilities) exposed |  |  | R$ 922 | 712
Percentage of decrease in US dollars |  |  | 7600.00% |
Percentage of decrease in euro |  | 155.00% |  |
Cash flow projection period |  | 12 months |  |
Daily liquidity projection period |  | 180 days |  |
Carrying value bond |  |  | R$ 14,777 | 14,772
Swap spread at the end |  |  | 1,705 |
Call spread at the endcall |  |  | 1,511 |
Swap comprising amount |  |  | R$ 3,216 |
Sensitivity analysis |  |  | the Company estimates that in a probable scenario the variation of the exchange rates of foreign currencies in relation to the Real at the end of 2020 will be an appreciation of the dollar by 29.01% to R$5.20. The Company has prepared a sensitivity analysis of the effects on the Company’s net income arising from depreciation of the Real exchange rate by 25%, and by 50%, in relation to this ‘probable’ scenario. |
TJLP [Member] |  |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |  |
Sensitivity analysis |  |  | Company estimates that, in a probable scenario, at December 31, 2020 Selic and TJLP rates will be 1.50% and 4.95%, respectively. |
Cemig Geracao Tres Marias Sa [Member] |  |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |  |
Maturity |  |  | 2024 |
Fair value of financial instruments |  |  | R$ 1,691 | 813
Carrying value bond |  |  | R$ 922 | R$ 712
Possible Scenario [Member] |  |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |  |
Risk-free interest rate |  |  | 25.00% |
Volatility |  |  | 50.00% |
Derivative hedge instrument, Assets |  |  | R$ 4,422 |
Derivative hedge instrument, Liabilities |  |  | 5,942 |
Net assets (liabilities) exposed |  |  | R$ (1,520) |

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