XML 116 R106.htm IDEA: XBRL DOCUMENT
v3.20.1

DEBENTURES - Summary (Details) R$ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 BRL (R$) instrument | Dec. 31, 2018 BRL (R$)
DEBENTURES |  |
Total Debentures | R$ 2,911,044 | R$ 1,538,873
Current debentures | 18,015 | 2,755
Non-current debentures | R$ 2,893,029 | 1,536,118
3rd- A and B |  |
DEBENTURES |  |
Total Debentures |  | 18,871
7th |  |
DEBENTURES |  |
Total Debentures |  | 1,102
8th |  |
DEBENTURES |  |
Total Debentures |  | 8,080
9th |  |
DEBENTURES |  |
Total Debentures |  | 2,349
11th - A and B |  |
DEBENTURES |  |
Total Debentures |  | 5,716
15th |  |
DEBENTURES |  |
Quantity Issued | instrument | 1,500,000 |
Total Debentures | R$ 1,504,436 | R$ 1,502,755
16th - A |  |
DEBENTURES |  |
Quantity Issued | instrument | 600,000 |
Total Debentures | R$ 602,847 |
16th - B |  |
DEBENTURES |  |
Quantity Issued | instrument | 800,000 |
Total Debentures | R$ 803,761 |

X
- Definition The number of debentures issued. + References No definition available. + Details
Name: | ggb_DebenturesNumberIssued
Namespace Prefix: | ggb_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of current notes and debentures issued and the current portion of non-current notes and debentures issued. [Refer: Notes and debentures issued] + 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_CurrentNotesAndDebenturesIssuedAndCurrentPortionOfNoncurrentNotesAndDebenturesIssued
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_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The non-current portion of non-current notes and debentures issued. [Refer: Notes and debentures issued] + 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_NoncurrentPortionOfNoncurrentNotesAndDebenturesIssued
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of notes and debentures issued by the entity. + 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_NotesAndDebenturesIssued
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceThirdMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceSeventhMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceEighthMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceNinthMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceEleventhMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceFifteenthMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceSixteenthaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=ggb_DebenturesIssuanceSixteenthBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |