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7. OTHER CURRENT AND NON-CURRENT ASSETS (Details Narrative ) R$ in Thousands | 12 Months Ended
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Dec. 31, 2019 BRL (R$)
Eletrobras's Compulsory Loan [Member] |
Disclosure of financial assets [line items] |
Recovery of additional credits | R$ 350,000

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- 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
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Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
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Period Type: | duration

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- Definition The amount of recovery of additional credits. + References No definition available. + Details
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Namespace Prefix: | sid_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |