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LOANS AND FINANCING - Additional Disclosures (Details) R$ in Thousands, $ in Millions | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2019 USD ($) | Dec. 31, 2019 BRL (R$) | Nov. 30, 2019 USD ($) | Oct. 31, 2019 BRL (R$) | Dec. 31, 2018 BRL (R$)
LOANS AND FINANCING |  |  |  |  |
Loans and financing |  | R$ 13,138,823 |  |  | R$ 13,367,841
Notional value |  | 12,958,565 |  |  | R$ 13,178,457
Gerdau Aominas |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Amount of outstanding balance credit facility | $ 70 | 282,000 |  |  |
GUSAP III LP |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Bonds issued |  | 2,015,000 | $ 500 |  |
Global Credit Line |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Loans and financing |  | 241,800 |  |  |
Amount of outstanding balance credit facility |  | 60,000 |  |  |
Maximum borrowing capacity |  | R$ 3,224,000 |  | R$ 800,000 |

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