Basis of consolidation (Details)	Dec. 31, 2012
Basis of consolidation
Voting capital (as a percent)	51.00%

Voting capital of principal consolidated operating subsidiaries.

No definition available.

Name:	vale_VotingCapitalOfPrincipalConsolidatedOperatingSubsidiaries
Namespace Prefix:	vale_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant