Stockholders' equity - Shareholders' Agreement (Details)	Aug. 14, 2017
Valepar Agreement
Shareholders Agreement
Percentage of shareholders that will be bind by a new shareholders' agreement post merger	20.00%

The percentage of shares acceptance of the proposal and the merger on a converted basis.

No definition available.

Name:	vale_PercentageOfShareholderThatWillBeBindOfPostMergerShareholdersAgreement
Namespace Prefix:	vale_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration