Quarterly report pursuant to Section 13 or 15(d)

Supplemental Guarantor Information (Condensed Consolidating Statement of Income) (Detail)

v2.4.0.6
Supplemental Guarantor Information (Condensed Consolidating Statement of Income) (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Schedule Of Condensed Consolidating Statement Of Operations [Line Items]        
Revenues $ 185,946 $ 245,371 $ 637,345 $ 709,148
Operating costs and expenses:        
Lease operating expenses 53,411 58,899 170,349 159,901
Production taxes 1,353 1,050 4,174 2,183
Gathering and transportation 2,810 4,853 11,140 13,203
Depreciation, depletion, amortization and accretion 77,462 84,455 251,894 241,917
General and administrative expenses 18,691 18,104 62,793 54,235
Derivative gain(loss) 24,659 (17,323) 14,421 (10,815)
Total costs and expenses 178,386 150,038 514,771 460,624
Operating income 7,560 95,333 122,574 248,524
Interest expense:        
Incurred 14,791 14,721 43,409 36,913
Capitalized (3,383) (3,163) (9,899) (6,654)
Loss on extinguishment of debt   2,031   22,694
Other income 202 6 210 22
Income (loss) before income tax expense (3,646) 81,750 89,274 195,593
Income tax expense (2,175) 28,822 33,959 68,841
Net income (1,471) 52,928 55,315 126,752
Parent Company [Member]
        
Schedule Of Condensed Consolidating Statement Of Operations [Line Items]        
Revenues 141,139 174,935 473,297 507,689
Operating costs and expenses:        
Lease operating expenses 47,353 49,854 150,860 130,001
Production taxes 1,353 1,050 4,174 2,183
Gathering and transportation 2,084 3,669 8,788 9,990
Depreciation, depletion, amortization and accretion 58,744 62,372 189,827 176,999
General and administrative expenses 18,691 18,104 60,200 51,653
Derivative gain(loss) 24,659 (17,323) 14,421 (10,815)
Total costs and expenses 152,884 117,726 428,270 360,011
Operating income (11,745) 57,209 45,027 147,678
Earnings of affiliates 12,551 24,780 50,395 65,550
Interest expense:        
Incurred 14,791 14,721 43,409 36,913
Capitalized (3,383) (3,163) (9,899) (6,654)
Loss on extinguishment of debt   2,031   22,694
Other income 202 6 210 22
Income (loss) before income tax expense (10,400) 68,406 62,122 160,297
Income tax expense (8,929) 15,478 6,807 33,545
Net income (1,471) 52,928 55,315 126,752
Guarantor Subsidiaries [Member]
        
Schedule Of Condensed Consolidating Statement Of Operations [Line Items]        
Revenues 44,807 70,436 164,048 201,459
Operating costs and expenses:        
Lease operating expenses 6,058 9,045 19,489 29,900
Gathering and transportation 726 1,184 2,352 3,213
Depreciation, depletion, amortization and accretion 18,718 22,083 62,067 64,918
General and administrative expenses     2,593 2,582
Total costs and expenses 25,502 32,312 86,501 100,613
Operating income 19,305 38,124 77,547 100,846
Interest expense:        
Income (loss) before income tax expense 19,305 38,124 77,547 100,846
Income tax expense 6,754 13,344 27,152 35,296
Net income 12,551 24,780 50,395 65,550
Eliminations [Member]
        
Operating costs and expenses:        
Earnings of affiliates (12,551) (24,780) (50,395) (65,550)
Interest expense:        
Income (loss) before income tax expense (12,551) (24,780) (50,395) (65,550)
Net income $ (12,551) $ (24,780) $ (50,395) $ (65,550)