XML 144 R113.htm IDEA: XBRL DOCUMENT
v3.20.1

FINANCIAL INSTRUMENTS - Swap Contracts (Details) R$ in Thousands, $ in Millions | Dec. 31, 2019 BRL (R$) | Dec. 31, 2018 USD ($) | Dec. 31, 2018 BRL (R$)
--- | --- | --- | ---
Swap Contracts |  |  |
Notional value | R$ 12,958,565 |  | R$ 13,178,457
Assets, Fair value |  |  |
Swap Contracts |  |  |
Amount receivable | R$ 2,846 |  | 33,417
Amount payable |  |  | (5,245)
Forward contract | Forward contracts maturing at 2019 long position |  |  |
Swap Contracts |  |  |
Notional value | $ |  | $ 19.2 |
Amount payable |  |  | (4,069)
Forward contract | Forward contracts maturing at 2019 short position |  |  |
Swap Contracts |  |  |
Notional value | $ |  | 18.3 |
Amount receivable |  |  | 462
Amount payable |  |  | (1,176)
Currency swap | Currency swap maturing in 2019 |  |  |
Swap Contracts |  |  |
Notional value | $ |  | $ 230.5 |
Amount receivable |  |  | R$ 30,249
Currency swap | Currency swap maturing in 2019 | CDI |  |  |
Swap Contracts |  |  |
Floating interest rate (as a percent) | 111.50% | 111.50% | 111.50%
Interest Rate Swap | Interest rate swap maturing in 2020 |  |  |
Swap Contracts |  |  |
Notional value | R$ 50,000 | $ 50.0 |
Amount receivable | R$ 2,846 |  | R$ 2,706
Interest Rate Swap | Interest rate swap maturing in 2020 | CDI |  |  |
Swap Contracts |  |  |
Floating interest rate (as a percent) | 111.50% | 111.50% | 111.50%

X
- Definition Variable interest rate in effect as of the balance sheet date related to the interest rate derivative. + References No definition available. + Details
Name: | ggb_IfrsDerivativeVariableInterestRate
Namespace Prefix: | ggb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DerivativeFinancialAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DerivativeFinancialLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition The nominal or face amount of a financial instrument, used to calculate payments made on that instrument. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_NotionalAmount
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_FinancialAssetsAtFairValueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_ForwardContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_HedgingInstrumentsAxis=ggb_ForwardContractsMaturingAt2019LongPositionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_HedgingInstrumentsAxis=ggb_ForwardContractsMaturingAt2019ShortPositionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_CurrencySwapContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_HedgingInstrumentsAxis=ggb_CurrencySwapMaturingIn2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TypesOfInterestRatesAxis=ggb_LocalInterbankDepositCertificateRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_InterestRateSwapContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_HedgingInstrumentsAxis=ggb_InterestRateSwapMaturingAt2020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |