XML 136 R117.htm IDEA: XBRL DOCUMENT
v3.21.1

14. FINANCIAL INSTRUMENTS (Details 9) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 BRL (R$)
Probable scenario [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | R$ (76,821) | [1]
Probable scenario [member] | 2/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (33,677) | [1]
Probable scenario [member] | 3/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (43,144) | [1]
Scenario 2 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (496,354) |
Scenario 2 [member] | 2/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (240,524) |
Scenario 2 [member] | 3/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (255,830) |
Scenario 1 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (248,177) |
Scenario 1 [member] | 2/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | (120,262) |
Scenario 1 [member] | 3/2/2021 [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Sensitivity analysis for price risks | R$ (127,915) |
[1] | The probable scenario was calculated considering the quotation of "Platts" on 1/14/2021 for the maturities of 2/2/2021 and 3/2/2021. Source Bloomberg.

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

X
- Definition The amount of sensitivity analysis for price risks. + References No definition available. + Details
Name: | sid_SensitivityAnalysisForPriceRisks
Namespace Prefix: | sid_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | ifrs-full_ProbabilityOfDefaultAxis=sid_ProbableScenarioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=sid_NotLaterThanOneYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProbabilityOfDefaultAxis=sid_ScenarioIITwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProbabilityOfDefaultAxis=sid_ScenarioIIThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |