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INTANGIBLE ASSETS - Intangible assets by segment (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | --- | ---
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | R$ 673,262 | R$ 836,096 | R$ 972,089 | R$ 1,319,941
Brazil |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 238,243 | 295,107 | 351,578 |
Special Steel |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 132,934 | 136,910 | 152,640 |
South America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 1,729 | 1,441 | 1,863 |
North America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | R$ 300,356 | R$ 402,638 | R$ 466,008 |

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