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RELATED-PARTY TRANSACTIONS - Intercompany loans (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
RELATED PARTY TRANSACTIONS |  |  |
Assets | R$ 134,354 | R$ 95,445 |
Liabilities | (22,855) | 0 |
Net financial income | 8,277 | 4,767 | R$ 545
Fundacao Gerdau |  |  |
RELATED PARTY TRANSACTIONS |  |  |
Assets | 17,262 | 21,838 |
Gerdau Corsa S.A.P.I de C.V. |  |  |
RELATED PARTY TRANSACTIONS |  |  |
Assets | 117,092 | R$ 73,607 |
Bradley Steel Processors |  |  |
RELATED PARTY TRANSACTIONS |  |  |
Liabilities | R$ (22,855) |  |

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