v2.4.0.8
Fair Value of Financial and Derivatives Instruments - Additional Information (Detail)
Jun. 30, 2013
bbl
Oil 2015 [Member]
 
Fair Value Of Financial Instruments [Line Items]  
Volume transacted in commodity derivatives position 2,600
Oil 2015 [Member] | Minimum [Member]
 
Fair Value Of Financial Instruments [Line Items]  
Contract price in commodity derivatives position 84.00
Oil 2015 [Member] | Maximum [Member]
 
Fair Value Of Financial Instruments [Line Items]  
Contract price in commodity derivatives position 91.00
Oil collars [Member]
 
Fair Value Of Financial Instruments [Line Items]  
Number of contracts 2