XML 102 R91.htm IDEA: XBRL DOCUMENT
v3.19.1

9. INVESTMENTS (Details Narrative) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure of fair value measurement of assets [line items] |  |
Expenses |  | R$ 1,380,193
Consorcio da Usina Hidrelectrica de Igarapava |  |
Disclosure of fair value measurement of assets [line items] |  |
Property, plant and equipment | R$ 23,596 | 24,759
Expenses | R$ 5,827 | R$ 5,966

X
- Definition Property, Plant and equipment less depreciation + References No definition available. + Details
Name: | SID_PropertyPlantAndEquipments
Namespace Prefix: | SID_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 73 -Subparagraph e -Clause vii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_73_e_vii&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 75 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_75_a&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_DepreciationPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=SID_ConsorcioDaUsinaHidrelectricaDeIgarapavaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |