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INTANGIBLE ASSETS - Intangible assets by segment (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | R$ 972,089 | R$ 1,319,941 | R$ 1,835,761 | R$ 1,547,098
Brazil |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 351,578 | 412,134 | 459,383 |
Special Steel |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 152,640 | 219,878 | 357,435 |
South America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | 1,863 | 7,606 | 13,507 |
North America |  |  |  |
Composition of other intangible assets by segment |  |  |  |
Other Intangibles | R$ 466,008 | R$ 680,323 | R$ 1,005,436 |

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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 2017-01-01 -Paragraph 118 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2017-03-01&anchor=para_118_e&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_c&doctype=Standard -URIDate 2017-03-09 + Details
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