XML 214 R195.htm IDEA: XBRL DOCUMENT
v3.21.1

30. EMPLOYEE BENEFITS (Details Narrative) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure of defined benefit plans [line items] |  |
Number of common shares held | 4,450,652 | 1,870,652
Total guarantee resources | R$ 5,700,000 | R$ 5,500,000
Percentage of average salary | 4.35% | 4.65%
Pension plan expense | R$ 41,050 | R$ 40,644
Description of investment policy | The investment plan is reviewed annually and approved by the Deliberative Council, considering a 5-year horizon, as established by CGPC resolution no. 7, of December 4, 2003. The investment limits and criteria established in the policy are based on Resolution 4,661 / 18, published by the National Monetary Council (“CMN”). |
Defined benefit plan [member] |  |
Disclosure of defined benefit plans [line items] |  |
Description of pension fund market | In compliance with current legislation, specific to the pension fund market, for the last 4 years ended (2017, 2018, 2019 and 2020), there was no need to pay installments by CSN, since the benefit plans defined actuarial gains in the year. |
Plan covering 35% Of The Average Salary [member] |  |
Disclosure of defined benefit plans [line items] |  |
Percentage of average salary | 35.00% |
Participant's salary term | 12 months |
Average Salary Supplementation Plan [member] |  |
Disclosure of defined benefit plans [line items] |  |
Percentage of average salary | 35.00% |
Participant's salary term | 12 months |
Mixed Supplementary Benefit Plan [member] | 2021 [member] |  |
Disclosure of defined benefit plans [line items] |  |
Contributions forecast to be paid 2020 | R$ 21,563 |
Contributions amount | R$ 1,322 |

X
- Definition The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 141 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_f&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_DisclosureOfDefinedBenefitPlansLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_147_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_148_d_iii&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_EstimateOfContributionsExpectedToBePaidToPlan
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Represent information about the description of investment policy. + References No definition available. + Details
Name: | sid_DescriptionOfInvestmentPolicy
Namespace Prefix: | sid_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represent information about the description of pension fund market. + References No definition available. + Details
Name: | sid_DescriptionOfPensionFundMarket
Namespace Prefix: | sid_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the number of common shares held. + References No definition available. + Details
Name: | sid_NumberOfSharesHeld
Namespace Prefix: | sid_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount refers to participants salary term. + References No definition available. + Details
Name: | sid_ParticipantsSalaryTerm
Namespace Prefix: | sid_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount refers to pension plan expense. + References No definition available. + Details
Name: | sid_PensionPlanExpense
Namespace Prefix: | sid_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount refers to plan assets. + References No definition available. + Details
Name: | sid_PlanAssetsValue
Namespace Prefix: | sid_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=sid_DefinedBenefitPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=sid_PlanCoveringThirtyFivePercentOfTheAverageSalaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=sid_AverageSalarySupplementationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=sid_MixedSupplementaryBenefitPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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