XML 286 R78.htm IDEA: XBRL DOCUMENT
v3.22.1

BUSINESS COMBINATION (Details Narrative) - BRL (R$) R$ in Millions | Aug. 31, 2021 | Dec. 31, 2021
--- | --- | ---
IfrsStatementLineItems [Line Items] |  |
Plan assets at fair value |  | R$ 567.3
Elizabeth Cimentos [Member] |  |
IfrsStatementLineItems [Line Items] |  |
Description of how acquirer obtained control of acquiree | On August 31, 2021, CSN Cimentos S.A. acquired 99.97% of the total capital stock of Elizabeth Mineração and 99.99% of the shares of Elizabeth Cimentos, with 88.746% of direct equity interest and 11.254% |

X
- Definition The description of how the acquirer obtained the power to govern the financial and operating policies of the acquiree so as to obtain benefits from its activities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2021-01-01 -Paragraph B64 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2021-en-r&anchor=para_B64_d&doctype=Appendix&subtype=B -URIDate 2021-03-24 + Details
Name: | ifrs-full_DescriptionOfHowAcquirerObtainedControlOfAcquiree
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | sid_IfrsStatementLineItems
Namespace Prefix: | sid_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | sid_PlanAssetsAtFairValue1
Namespace Prefix: | sid_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_BusinessCombinationsAxis=sid_ElizabethCimentosMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |