Annual report pursuant to Section 13 and 15(d)

Estimated Quantities of Net Proved, Proved Developed and Proved Undeveloped Oil, Ngls and Natural Gas Reserves (Parenthetical) (Detail)

v2.4.0.8
Estimated Quantities of Net Proved, Proved Developed and Proved Undeveloped Oil, Ngls and Natural Gas Reserves (Parenthetical) (Detail)
12 Months Ended
Dec. 31, 2012
Changes due to price
Mcfe
Dec. 31, 2011
Changes due to price
Mcfe
Dec. 31, 2011
Changes due to marketing arrangement
Mcfe
Dec. 31, 2011
Changes at Tahoe field for compressor project
Mcfe
Dec. 31, 2011
Changes at the Fairway field
Mcfe
Dec. 31, 2011
Changes at the Main Pass 98 field
Mcfe
Dec. 31, 2013
Changes at the Ship Shoal 349/359 field
Mcfe
Dec. 31, 2011
Changes at the Ship Shoal 349/359 field
Mcfe
Dec. 31, 2011
Changes at the Main Pass 108 field
Mcfe
Dec. 31, 2013
Changes at the Spraberry field
Mcfe
Dec. 31, 2012
Changes at the Spraberry field
Mcfe
Dec. 31, 2012
Changes at the High Island 22 field
Mcfe
Dec. 31, 2013
Changes due to price
Mcfe
Dec. 31, 2013
Changes at the High Island 22 field
Mcfe
Dec. 31, 2013
Changes at the Main Pass 98 field
Mcfe
Dec. 31, 2013
Changes at the South Timbalier 314 field
Mcfe
Dec. 31, 2013
Changes at the Main Pass 108 field
Mcfe
Dec. 31, 2013
Changes at the South Timbalier 176 field
Mcfe
Dec. 31, 2013
Changes at the Mississippi Canyon 698 field
Mcfe
Reserve Quantities [Line Items]                                      
Revisions of previous estimates (8,000,000) 6,300,000 16,500,000 11,300,000 10,600,000   (7,900,000)     (29,600,000) (17,900,000)   11,300,000 (13,900,000) 4,300,000 4,000,000 3,500,000 3,200,000  
Extensions and discoveries           13,900,000 25,300,000 8,000,000 3,700,000 75,400,000 69,500,000 16,200,000             11,500,000