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Derivative Financial Instruments - Summary of Gain (Loss) Recognized in Income on Oil and Gas Commodity Contracts on (Detail) | 3 Months Ended
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Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items] |
Document Period End Date | Dec. 31, 2013

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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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- Details
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