Derivative Instruments - Summary of Outstanding Contracts with Respect to Crude Oil (Detail) - ICE Brent [Member] - Call Option October 2016 to December 2016 [Member]	9 Months Ended
Sep. 30, 2016 $ / bbl bbl
Derivative [Line Items]
Oil Production Derivative Volume \| bbl	368,000
Derivative, Average Price Risk Option Strike Price \| $ / bbl	107.70

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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