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SHORT-TERM DEBT AND LONG-TERM DEBT - Additional disclosures (Details) R$ in Thousands, $ in Millions | Dec. 31, 2020 USD ($) | Dec. 31, 2020 BRL (R$) | Dec. 31, 2019 BRL (R$) | Oct. 31, 2019 BRL (R$)
--- | --- | --- | --- | ---
LOANS AND FINANCING |  |  |  |
Loans and financing |  | R$ 14,612,934 | R$ 13,138,823 |
Working capital |  |  |  |
LOANS AND FINANCING |  |  |  |
Loans and financing |  | 1,178,557 | R$ 107,312 |
Global Credit Line |  |  |  |
LOANS AND FINANCING |  |  |  |
Amount of outstanding balance credit facility | $ 40 | 207,000 |  |
Maximum borrowing capacity |  | 4,157,000 |  | R$ 800,000
Bonds | Gerdau Acos Longos and Gerdau Acominas |  |  |  |
LOANS AND FINANCING |  |  |  |
Principal amount | $ | $ 300 |  |  |
Amount outstanding |  | R$ 1,175 |  |

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