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LOANS AND FINANCING - Additional Disclosures (Details) R$ in Thousands, $ in Millions | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Oct. 31, 2017 BRL (R$) | Dec. 31, 2017 USD ($) tranche | Dec. 31, 2017 BRL (R$) tranche | Dec. 31, 2016 BRL (R$) | Jun. 30, 2009 BRL (R$)
LOANS AND FINANCING |  |  |  |  |
Notional value |  |  | R$ 16,207,120 | R$ 20,049,854 |
Loans and financing |  |  | 16,461,656 | R$ 20,417,810 |
Ten Year Bonds | Gerdau Trade Inc. |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Notional value | R$ 650,000 |  |  |  |
Debt instrument term | 10 years |  |  |  |
Coupon rate | 4.875% |  |  |  |
FINAME/BNDES program |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Loan amount guaranteed by asset being financed |  |  | R$ 110,400 |  |
Credit line with BNDES |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Maximum borrowing capacity |  |  |  |  | R$ 1,500,000
Interest rate basis |  | TJLP |  |  |
Adjustment to interest rate basis (as a percent) |  | 2.16% | 2.16% |  |
Loans and financing |  |  | R$ 402,500 |  |
Senior Unsecured Global Working Capital Credit Agreement |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Maximum borrowing capacity |  | $ 800.0 | R$ 2,646,400 |  |
Number of tranches | tranche |  | 2 | 2 |  |
Loans and financing |  | $ 54.0 | R$ 178,600 |  |
Senior Unsecured Global Working Capital Credit Agreement | Gerdau's North American subsidiaries |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Maximum borrowing capacity |  | 200.0 | 661,600 |  |
Senior Unsecured Global Working Capital Credit Agreement | Gerdau's Latin American subsidiaries |  |  |  |  |
LOANS AND FINANCING |  |  |  |  |
Maximum borrowing capacity |  | $ 600.0 | R$ 2,028,000 |  |

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