No definition available.

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Gains (losses) on assets held for sale and sales of interest in subsidiaries and associates.

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No definition available.

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- Definition

The number of hydroelectric plants.

+ References

No definition available.

+ Details

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The number of production plants.

+ References

No definition available.

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- Definition

The number of rebar-producing mills.

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No definition available.

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The percentage of ownership interest in subsidiary sold.

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No definition available.

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The fair value, as of the date of change of investment entity status, of subsidiaries that cease to be consolidated. [Refer: At fair value [member]; Disclosure of investment entities [text block]; Subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The cash inflow from the disposal of non-current assets or disposal groups classified as held for sale and discontinued operations. [Refer: Discontinued operations [member]; Disposal groups classified as held for sale [member]; Non-current assets or disposal groups classified as held for sale]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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CONSOLIDATED FINANCIAL STATEMENTS - Gains and losses on assets held for sale and sale of interest in subsidiaries (Details) R$ in Thousands, $ in Millions							12 Months Ended
	Nov. 05, 2018 USD ($) item	Oct. 31, 2018 USD ($)	Jul. 31, 2018 BRL (R$) item	Jun. 29, 2018 USD ($) Plant	Mar. 30, 2018 USD ($)	Mar. 30, 2018 BRL (R$)	Dec. 31, 2020 BRL (R$)	Dec. 31, 2019 BRL (R$)	Dec. 31, 2018 BRL (R$)	Nov. 05, 2018 BRL (R$)	Oct. 31, 2018 BRL (R$)	Jun. 29, 2018 BRL (R$)
Gains and losses on assets held for sale and sales of interest in subsidiaries
Expenses attributable to assets held for sale and sales of interest in subsidiaries \| R$							R$ 0	R$ 0	R$ 414,507
Optimus Steel LLC
Gains and losses on assets held for sale and sales of interest in subsidiaries
Proceeds from sale					$ 99.5	R$ 330,700
Aza Participacoes SpA and subsidiaries
Gains and losses on assets held for sale and sales of interest in subsidiaries
Proportion of ownership interest in subsidiary sold				100.00%
Number of production plants \| Plant				3
Total value of sale				$ 154.1								R$ 594,200
Cacu and Barra dos Coqueiros hydroelectric plants
Gains and losses on assets held for sale and sales of interest in subsidiaries
Number of hydroelectric plants \| item			2
Proceeds from sale \| R$			R$ 835,000
Gerdau Hungria KFT Y CIA Sociedad Regular Colectiva
Gains and losses on assets held for sale and sales of interest in subsidiaries
Proportion of ownership interest in subsidiary sold		98.89%
Total value of sale		$ 120.0									R$ 490,200
Gerdau Hungria KFT Y CIA Sociedad Regular Colectiva \| INDIA
Gains and losses on assets held for sale and sales of interest in subsidiaries
Proportion of ownership interest in subsidiary sold		100.00%
Sale of production units and distribution centers in the U.S.
Gains and losses on assets held for sale and sales of interest in subsidiaries
Number of rebar-producing mills \| item	4
Total value of sale	$ 600.0									R$ 2,222,900