XML 92 R67.htm IDEA: XBRL DOCUMENT v3.22.1

CONSOLIDATED FINANCIAL STATEMENTS - Results in operations with subsidiary and joint ventures (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of Significant Investments in Subsidiary and Joint Ventures [Line Items]
Recycling to income of the cumulative translation adjustments	R$ (193,334)	R$ 0	R$ 0
Write-off of goodwill	(549,898)
Results in operations with subsidiary and joint ventures	(162,913)	R$ 0	R$ 0
Gerdau Corsa S.A.P.I de C.V. | North America Operation
Disclosure of Significant Investments in Subsidiary and Joint Ventures [Line Items]
Write-off of goodwill	549,898
Results in operations with subsidiary and joint ventures	R$ 162,913
Gerdau Corsa S.A.P.I de C.V. | Minimum
Disclosure of Significant Investments in Subsidiary and Joint Ventures [Line Items]
Equity Interests (as a percent)	70.00%
Gerdau Corsa S.A.P.I de C.V. | Maximum
Disclosure of Significant Investments in Subsidiary and Joint Ventures [Line Items]
Equity Interests (as a percent)	75.00%
Sidertul, S.A. de C.V.
Disclosure of Significant Investments in Subsidiary and Joint Ventures [Line Items]
Gain due to the fair value adjustment of the interest held	R$ 193,651
Recycling to income of the cumulative translation adjustments	R$ 193,334

X

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ggb_DisclosureOfSignificantInvestmentsInSubsidiaryAndJointVenturesLineItems
Namespace Prefix:	ggb_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The gains (losses) from changes in the fair value of equity method investments.

+ References

No definition available.

+ Details

Name:	ggb_GainsLossesOnFairValueAdjustmentEquityMethodInvestments
Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of increase (decrease) through Results in Operations with Subsidiary and Joint Ventures, Goodwill.

+ References

No definition available.

+ Details

Name:	ggb_IncreaseDecreaseThroughResultsInOperationsWithSubsidiaryAndJointVenturesGoodwill
Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The proportion of ownership interest in a joint operation attributable to the entity. [Refer: Joint operations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2021-01-01
-Paragraph 21
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_21_a_iv&doctype=Standard
-URIDate 2021-03-24

+ Details

Name:	ifrs-full_ProportionOfOwnershipInterestInJointOperation
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of reclassification adjustments related to exchange differences when the financial statements of foreign operations are translated, net of tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 21
-IssueDate 2021-01-01
-Paragraph 48
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2021-en-r&anchor=para_48&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 92
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_92&doctype=Standard
-URIDate 2021-03-24

+ Details

Name:	ifrs-full_ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationNetOfTax
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The entity's share of the profit (loss) of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 23
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23_g&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 28
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_e&doctype=Standard
-URIDate 2021-03-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective on first application of IFRS 9
-Name IFRS
-Number 4
-IssueDate 2021-01-01
-Paragraph 39M
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=4&code=ifrs-tx-2021-en-b&anchor=para_39M_b&doctype=Standard
-URIDate 2021-03-24

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 82
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_82_c&doctype=Standard
-URIDate 2021-03-24

+ Details

Name:	ifrs-full_ShareOfProfitLossOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	ifrs-full_SignificantInvestmentsInSubsidiariesAxis=ggb_GerdauCorsaSapiDeCvMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_SegmentsAxis=ggb_NorthAmericaSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_SignificantInvestmentsInSubsidiariesAxis=ggb_SidertulS.a.DeC.v.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: