Annual report pursuant to Section 13 and 15(d)

Condensed Consolidating Statement of Income (Detail)

v2.4.0.6
Condensed Consolidating Statement of Income (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2012
Sep. 30, 2012
Jun. 30, 2012
Mar. 31, 2012
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Schedule of Condensed Consolidating Statement of Operations [Line Items]                      
Revenues $ 237,146 $ 185,946 $ 215,513 $ 235,886 $ 261,899 $ 245,371 $ 252,922 $ 210,855 $ 874,491 $ 971,047 $ 705,783
Operating costs and expenses:                      
Lease operating expenses                 232,260 219,206 169,670
Production taxes                 5,840 4,275 1,194
Gathering and transportation                 14,878 16,920 16,484
Depreciation, depletion and amortization                 336,177 299,015 268,415
Asset retirement obligation accretion                 20,055 29,771 25,685
General and administrative expenses                 82,017 74,296 53,290
Derivative (gain) loss                 13,954 (1,896) 4,256
Total costs and expenses                 705,181 641,587 538,994
Operating income 46,737 7,560 99,100 15,913 80,936 95,333 115,643 37,548 169,310 329,460 166,789
Interest expense:                      
Incurred                 63,268 52,393 43,101
Capitalized                 (13,274) (9,877) (5,395)
Loss on extinguishment of debt                    22,694   
Other income                 215 84 710
Income before income tax expense                 119,531 264,334 129,793
Income tax expense (benefit)                 47,547 91,517 11,901
Net income 16,670 (1,471) 53,567 3,218 46,065 52,928 55,175 18,649 71,984 172,817 117,892
Parent Company
                      
Schedule of Condensed Consolidating Statement of Operations [Line Items]                      
Revenues                 659,203 697,899 608,600
Operating costs and expenses:                      
Lease operating expenses                 209,581 182,165 152,534
Production taxes                 5,840 4,275 1,194
Gathering and transportation                 11,703 12,676 15,338
Depreciation, depletion and amortization                 253,807 214,740 241,105
Asset retirement obligation accretion                 17,463 26,947 25,122
General and administrative expenses                 79,424 71,714 51,662
Derivative (gain) loss                 13,954 (1,896) 4,256
Total costs and expenses                 591,772 510,621 491,211
Operating income                 67,431 187,278 117,389
Earnings of affiliates                 66,195 92,533 32,110
Interest expense:                      
Incurred                 63,268 52,393 43,101
Capitalized                 (13,274) (9,877) (5,395)
Loss on extinguishment of debt                   22,694  
Other income                 215 84 710
Income before income tax expense                 83,847 214,685 112,503
Income tax expense (benefit)                 11,863 41,868 (5,389)
Net income                 71,984 172,817 117,892
Guarantor Subsidiaries
                      
Schedule of Condensed Consolidating Statement of Operations [Line Items]                      
Revenues                 215,288 273,148 97,183 [1]
Operating costs and expenses:                      
Lease operating expenses                 22,679 37,041 17,136 [1]
Gathering and transportation                 3,175 4,244 1,146 [1]
Depreciation, depletion and amortization                 82,370 84,275 27,310 [1]
Asset retirement obligation accretion                 2,592 2,824 563 [1]
General and administrative expenses                 2,593 2,582 1,628 [1]
Total costs and expenses                 113,409 130,966 47,783 [1]
Operating income                 101,879 142,182 49,400 [1]
Interest expense:                      
Income before income tax expense                 101,879 142,182 49,400 [1]
Income tax expense (benefit)                 35,684 49,649 17,290 [1]
Net income                 66,195 92,533 32,110 [1]
Eliminations
                      
Operating costs and expenses:                      
Earnings of affiliates                 (66,195) (92,533) (32,110)
Interest expense:                      
Income before income tax expense                 (66,195) (92,533) (32,110)
Net income                 $ (66,195) $ (92,533) $ (32,110)
[1] Began operations on May 1, 2010.