Quarterly report pursuant to Section 13 or 15(d)

Statement of Operations (Detail)

v2.4.0.6
Statement of Operations (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Dec. 31, 2011
Condensed Financial Statements [Line Items]          
Total revenues $ 165,301 $ 176,589 $ 520,795 $ 505,580  
Operating expenses 101,484 99,042 300,942 311,100  
Depreciation and amortization 29,779 27,581 85,357 82,511  
Total operating gross margin 34,038 49,966 134,496 111,969 11,700
General and administration expense (1) (8,905) [1] (8,630) (21,822) [1] (23,384)  
Gain on disposition of assets, net 606 623 2,466 1,993  
Total operating income (loss) 25,739 41,959 115,140 90,578  
Other income and (expense):          
Interest expense (8,171) (5,591) (25,133) (17,208)  
Changes in fair value of derivative positions 19 (49) 8 (186)  
Interest income 30 29 109 208  
Loss on extinguishment of debt (117)   (1,766)    
Other 26 (657) 62 (522)  
Total other expense (8,213) (6,268) (26,720) (17,708)  
Income (benefit) before income taxes 17,526 35,691 88,420 72,870  
Total income tax expense (benefit) 6,695 15,042 31,155 33,345  
Net income (loss) 10,831 20,649 57,265 39,525  
Less: Net income (loss) attributable to noncontrolling interest (105) (76) (146) (202)  
Net income (loss) attributable to controlling interest 10,936 20,725 57,411 39,727  
Parent [Member]
          
Condensed Financial Statements [Line Items]          
General and administration expense (1) (47) [1] (45) (137) [1] (173)  
Total operating income (loss) (47) (45) (137) (173)  
Other income and (expense):          
Interest expense (9,105) (6,709) (27,923) (20,307)  
Changes in fair value of derivative positions 19 (49) 8 (186)  
Interest income 95 124 8,695 18,065  
Loss on extinguishment of debt (117)   (1,766)    
Equity in net earnings of subsidiaries 10,596 25,361 61,553 66,120  
Total other expense 1,488 18,727 40,567 63,692  
Income (benefit) before income taxes 1,441 18,682 40,430 63,519  
Total income tax expense (benefit) (9,495) (2,043) (16,981) 23,792  
Net income (loss) 10,936 20,725 57,411 39,727  
Net income (loss) attributable to controlling interest 10,936 20,725 57,411 39,727  
Guarantor [Member]
          
Condensed Financial Statements [Line Items]          
Total revenues 98,969 98,687 302,892 281,527  
Operating expenses 45,850 41,823 136,849 133,451  
Depreciation and amortization 17,866 16,124 49,127 46,721  
Total operating gross margin 35,253 40,740 116,916 101,355  
General and administration expense (1) (8,823) [1] (8,454) (21,273) [1] (22,949)  
Gain on disposition of assets, net 553 233 1,168 1,137  
Total operating income (loss) 26,983 32,519 96,811 79,543  
Other income and (expense):          
Interest expense (43) (35) (115) (17,854)  
Interest income 179 188 4,894 568  
Other 26 (657) 64 (536)  
Total other expense 162 (504) 4,843 (17,822)  
Income (benefit) before income taxes 27,145 32,015 101,654 61,721  
Total income tax expense (benefit) 10,451 12,490 38,149 20,543  
Net income (loss) 16,694 19,525 63,505 41,178  
Net income (loss) attributable to controlling interest 16,694 19,525 63,505 41,178  
Non-Guarantor [Member]
          
Condensed Financial Statements [Line Items]          
Total revenues 94,749 105,807 295,811 314,221  
Operating expenses 84,051 85,124 242,001 267,817  
Depreciation and amortization 11,913 11,457 36,230 35,790  
Total operating gross margin (1,215) 9,226 17,580 10,614  
General and administration expense (1) (35) [1] (131) (412) [1] (262)  
Gain on disposition of assets, net 53 390 1,298 856  
Total operating income (loss) (1,197) 9,485 18,466 11,208  
Other income and (expense):          
Interest expense (1,840) (3,051) (5,811) (6,939)  
Interest income 2,573 3,921 39,345 9,467  
Other     (2) 14  
Total other expense 733 870 33,532 2,542  
Income (benefit) before income taxes (464) 10,355 51,998 13,750  
Total income tax expense (benefit) 5,739 4,595 9,987 (10,990)  
Net income (loss) (6,203) 5,760 42,011 24,740  
Less: Net income (loss) attributable to noncontrolling interest (105) (76) (146) (202)  
Net income (loss) attributable to controlling interest (6,098) 5,836 42,157 24,942  
Eliminations [Member]
          
Condensed Financial Statements [Line Items]          
Total revenues (28,417) (27,905) (77,908) (90,168)  
Operating expenses (28,417) (27,905) (77,908) (90,168)  
Other income and (expense):          
Interest expense 2,817 4,204 8,716 27,892  
Interest income (2,817) (4,204) (52,825) (27,892)  
Equity in net earnings of subsidiaries (10,596) (25,361) (61,553) (66,120)  
Total other expense (10,596) (25,361) (105,662) (66,120)  
Income (benefit) before income taxes (10,596) (25,361) (105,662) (66,120)  
Net income (loss) (10,596) (25,361) (105,662) (66,120)  
Net income (loss) attributable to controlling interest $ (10,596) $ (25,361) $ (105,662) $ (66,120)  
[1] General and administration expenses for field operations are included in operating expenses.