XML 102 R98.htm IDEA: XBRL DOCUMENT
v3.20.1

RIGHT-OF-USE ASSETS AND LEASE LIABILITY - Summary of changes in the leasing assets (Details) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 BRL (R$)
Summary of changes in the Right-of-use assets |
Balances at the end of the year | R$ 777,314
Gross |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year | 836,368
Additions | 143,521
Disposals | (35,555)
Remeasurements | 32,212
Foreign exchange effect | 10,589
Balances at the end of the year | 987,135
Accumulated impairment losses |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year |
Depreciation | (214,771)
Disposals | 6,588
Foreign exchange effect | (1,638)
Balances at the end of the year | (209,821)
Land and buildings |
Summary of changes in the Right-of-use assets |
Balances at the end of the year | 234,511
Land and buildings | Gross |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year | 243,250
Additions | 14,062
Disposals | (10,493)
Remeasurements | 33,322
Foreign exchange effect | 3,853
Balances at the end of the year | 283,994
Land and buildings | Accumulated impairment losses |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year |
Depreciation | (50,080)
Disposals | 1,330
Foreign exchange effect | (733)
Balances at the end of the year | (49,483)
Machines equipment and installations |
Summary of changes in the Right-of-use assets |
Balances at the end of the year | 410,009
Machines equipment and installations | Gross |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year | 436,401
Additions | 117,653
Disposals | (22,993)
Remeasurements | (2,346)
Foreign exchange effect | 4,571
Balances at the end of the year | 533,286
Machines equipment and installations | Accumulated impairment losses |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year |
Depreciation | (127,399)
Disposals | 4,250
Foreign exchange effect | (128)
Balances at the end of the year | (123,277)
Data electronic equipment |
Summary of changes in the Right-of-use assets |
Balances at the end of the year | 92,017
Data electronic equipment | Gross |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year | 106,787
Additions | 742
Disposals | (162)
Foreign exchange effect | 46
Balances at the end of the year | 107,413
Data electronic equipment | Accumulated impairment losses |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year |
Depreciation | (15,419)
Disposals | 32
Foreign exchange effect | (9)
Balances at the end of the year | (15,396)
Others |
Summary of changes in the Right-of-use assets |
Balances at the end of the year | 40,777
Others | Gross |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year | 49,930
Additions | 11,064
Disposals | (1,907)
Remeasurements | 1,236
Foreign exchange effect | 2,119
Balances at the end of the year | 62,442
Others | Accumulated impairment losses |
Summary of changes in the Right-of-use assets |
Balances at the beginning of the year |
Depreciation | (21,873)
Disposals | 976
Foreign exchange effect | (768)
Balances at the end of the year | R$ (21,665)

X
- Definition The amount of disposals to right-of-use assets. + References No definition available. + Details
Name: | ggb_DisposalsToRightOfUseAssets
Namespace Prefix: | ggb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of foreign exchange effect to right-of-use assets. + References No definition available. + Details
Name: | ggb_ForeignExchangeTranslationEffectToRightOfUseAssets
Namespace Prefix: | ggb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount increase (decrease) through remeasurements to right-of-use assets. + References No definition available. + Details
Name: | ggb_IncreaseDecreaseThroughRemeasurementsRightOfUseAssets
Namespace Prefix: | ggb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of additions to right-of-use assets. [Refer: Right-of-use assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_h&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_AdditionsToRightofuseAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of depreciation of right-of-use assets. [Refer: Depreciation and amortisation expense; Right-of-use assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_a&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DepreciationRightofuseAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
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_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph j -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_j&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_RightofuseAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_GrossCarryingAmountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_AccumulatedImpairmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfAssetsAxis=ifrs-full_LandAndBuildingsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfAssetsAxis=ggb_MachinesEquipmentAndInstallationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfAssetsAxis=ggb_DataElectronicEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfAssetsAxis=ifrs-full_OtherAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |