Commitments and contingencies (Details) (Vale New Caledonia S.A.S., USD $)	12 Months Ended
Dec. 31, 2011
Option to purchase shares of VNC \| Sumic
Description of put option and other commitments
Percentage of shares held by Sumic Nickel Netherlands B.V in VNC	21.00%
Lowest level of shares to be sold (as a percent of shares owned)	25.00%
Medium level of shares to be sold (as a percent of shares owned)	50.00%
Highest level of shares to be sold (as a percent of shares owned)	100.00%
The period over which the prescribed process occurs	5 months
Put option exercise description	$ 4,600,000,000
Bank Guarantee
Description of put option and other commitments
Letters of credit and guarantees	$ 465,000,000

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_PurchaseCommitmentExcludingLongtermCommitmentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the details pertaining o letters of credit and guarantees.

+ References

No definition available.

+ Details

Name:	vale_OutstandingLettersOfCreditAndGuarantees
Namespace Prefix:	vale_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the lowest level of percentage of shares owned by a third party which the entity is required to purchase, based on project funding estimates.

+ References

No definition available.

+ Details

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

- Definition

Represents the highest level of percentage of shares owned by a third party which the entity is required to purchase, based on project funding estimates.

+ References

No definition available.

+ Details

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

- Definition

Represents the middle level of percentage of shares owned by a third party which the entity is required to purchase, based on project funding estimates.

+ References

No definition available.

+ Details

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

- Definition

Represents the period over which the prescribed process occurs.

+ References

No definition available.

+ Details

Name:	vale_PeriodOfPrescribedProcessOccurs
Namespace Prefix:	vale_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the threshold amount of project funding which could trigger the put option.

+ References

No definition available.

+ Details

Name:	vale_PutOptionTriggerProjectFunding
Namespace Prefix:	vale_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant