Brumadinho dam failure - Assets write-off (Details) - 12 months ended Dec. 31, 2019 R$ in Millions, $ in Millions	BRL (R$)	USD ($)
Corrego do Feijao mine and upstream dams
Brumadinho dam failure
Impairment loss	R$ 904	$ 235

The amount recognised as a reduction of the carrying amount of an asset or cash-generating unit to its recoverable amount. [Refer: Carrying amount [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2019-01-01
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-Subparagraph b
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-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=36&code=ifrs-tx-2019-en-r&anchor=para_130_d_ii&doctype=Standard
-URIDate 2019-03-27

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