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INTANGIBLE ASSETS - Intangible assets by segment (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | ---
Composition of other intangible assets by segment |  |  |  |
Other intangible assets | R$ 622,578 | R$ 673,262 | R$ 836,096 | R$ 972,089
Brazil |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other intangible assets | 220,303 | 238,243 | 295,107 |
Special Steel |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other intangible assets | 156,557 | 132,934 | 136,910 |
South America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other intangible assets | 1,534 | 1,729 | 1,441 |
North America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other intangible assets | R$ 244,184 | R$ 300,356 | R$ 402,638 |

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- Definition The amount of identifiable non-monetary assets without physical substance. This amount does not include goodwill. [Refer: Goodwill] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 38 -IssueDate 2020-01-01 -Paragraph 118 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=38&code=ifrs-tx-2020-en-r&anchor=para_118_e&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 54 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_54_c&doctype=Standard -URIDate 2020-01-01 + Details
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