XML 148 R125.htm IDEA: XBRL DOCUMENT v3.21.1

RELATED-PARTY TRANSACTIONS - Operations with related parties (Details) R$ in Thousands	12 Months Ended
	Dec. 31, 2020 BRL (R$) installment	Dec. 31, 2019 BRL (R$)	Dec. 31, 2018 BRL (R$)
Associate companies and joint ventures
RELATED PARTY TRANSACTIONS
Sales to related parties	R$ 887,945	R$ 1,572,618	R$ 1,382,584
Purchases from related parties	208,948	198,636	129,513
Sales to related parties, net of purchases	678,997	1,373,982	1,253,071
Controlling shareholders
RELATED PARTY TRANSACTIONS
Sale of property to related party	R$ 21,204
Number of annual installments | installment	6
Annual installment amount	R$ 3,534
Accounts receivable from sale of property to related party	17,670
Rental income from related party	R$ 524	R$ 554	R$ 445
Guarantee fee percentage	0.95%	0.95%	0.95%
Expenses resulting from debenture guarantees		R$ 68	R$ 194

X

- Definition

The amount of accounts receivables resulting from a sale of property to a related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The amount of each annual installment payment to be received under the terms of agreement in the sale of property.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Reflects the guarantee fee as a percentage on the amount of debentures guaranteed.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The expense related to the guarantee of debentures.

+ References

No definition available.

+ Details

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

X

- Definition

The fair value of property sold to a related party as of the date of sale.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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X

- Definition

The net revenue (purchases) from transactions with related parties.

+ References

No definition available.

+ Details

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

X

- Definition

The number of annual installments over which payments are to be received under the terms of agreement in the sale of property.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of rental income resulting from agreements with a related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	ggb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

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X

- Definition

The amount of goods purchased by the entity in related party transactions. [Refer: Related parties [member]]

+ References

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Balance Type:	debit
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- Definition

The amount of revenue arising from the sale of goods in related party transactions. [Refer: Revenue; Related parties [member]]

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Balance Type:	credit
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- Details

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- Details

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