COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	9 Months Ended
May 31, 2010	Sep. 30, 2012 Contract LawSuits
Contingencies And Commitments [Line Items]
Accrued liability for legal contingencies		$ 20
Number of Potential class action lawsuits are pending in respect of oil and gas royalties paid by the Company		2
Cost for the restoration of plaintiffs' property	87
Long term contracts unenforceable as penalty		2
Undiscounted reserve for environmental remediation		$ 102

Undiscounted amount of the accrual for environmental loss contingencies.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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-Name Accounting Standards Codification

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