Annual report pursuant to Section 13 and 15(d)

Supplemental Guarantor Information (Condensed Consolidating Balance Sheet) (Details)

v2.4.0.6
Supplemental Guarantor Information (Condensed Consolidating Balance Sheet) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2008
Cash and cash equivalents $ 4,512 $ 28,655 $ 38,187 $ 357,552
Oil and natural gas sales 98,550 79,911    
Joint interest and other 25,089 25,415    
Insurance 715 1,014    
Income taxes          
Total receivables 124,354 106,340    
Deferred income taxes 2,007 5,784    
Prepaid expenses and other assets 30,315 23,426    
Total current assets 161,188 164,205    
Oil and natural gas properties and equipment 5,959,016 5,225,582    
Furniture, fixtures and other 19,500 15,841    
Total property and equipment 5,978,516 5,241,423    
Less accumulated depreciation, depletion and amortization 4,320,410 4,021,395    
Net property and equipment 1,658,106 1,220,028    
Restricted deposits for asset retirement obligations 33,462 30,636    
Deferred income taxes    2,819    
Other assets 16,169 6,406    
Total assets 1,868,925 1,424,094    
Accounts payable 75,871 80,442    
Undistributed oil and natural gas proceeds 33,732 25,240    
Asset retirement obligations 138,185 92,575    
Accrued liabilities 29,705 25,827    
Income taxes 10,392 17,552    
Total current liabilities 287,885 241,636    
Long-term debt 717,000 450,000    
Asset retirement obligations, less current portion 255,695 298,741    
Deferred income taxes 58,881      
Other liabilities 4,890 11,974    
Commitments and contingencies          
Common stock 1 1    
Additional paid-in capital 386,920 377,529    
Retained earnings 181,820 68,380    
Treasury stock, at cost (24,167) (24,167) (24,200)  
Total shareholders' equity 544,574 421,743    
Total liabilities and shareholders' equity 1,868,925 1,424,094    
Parent Company [Member]
        
Cash and cash equivalents 4,512 28,655 38,187  
Oil and natural gas sales 78,131 50,421    
Joint interest and other 25,089 25,415    
Insurance 715 1,014    
Income taxes 74,183 2,492    
Total receivables 178,118 79,342    
Deferred income taxes 2,007 5,784    
Prepaid expenses and other assets 30,315 23,426    
Total current assets 214,952 137,207    
Oil and natural gas properties and equipment 5,689,535 4,955,460    
Furniture, fixtures and other 19,500 15,841    
Total property and equipment 5,709,035 4,971,301    
Less accumulated depreciation, depletion and amortization 4,208,825 3,994,085    
Net property and equipment 1,500,210 977,216    
Restricted deposits for asset retirement obligations 33,462 30,636    
Deferred income taxes    2,819    
Other assets 372,572 275,461    
Total assets 2,121,196 1,423,339    
Accounts payable 73,333 77,422    
Undistributed oil and natural gas proceeds 33,391 24,866    
Asset retirement obligations 138,185 92,575    
Accrued liabilities 29,705 25,827    
Total current liabilities 274,614 220,690    
Long-term debt 717,000 450,000    
Asset retirement obligations, less current portion 228,419 269,016    
Deferred income taxes 76,518 2,755    
Other liabilities 280,071 59,135    
Commitments and contingencies          
Common stock 1 1    
Additional paid-in capital 386,920 377,529    
Retained earnings 181,820 68,380    
Treasury stock, at cost (24,167) (24,167)    
Total shareholders' equity 544,574 421,743    
Total liabilities and shareholders' equity 2,121,196 1,423,339    
Guarantor Subsidiaries [Member]
        
Cash and cash equivalents      [1]    [1]  
Oil and natural gas sales 20,419 29,490 [1]    
Joint interest and other      [1]    
Insurance      [1]    
Income taxes       [1]    
Total receivables 20,419 29,490 [1]    
Deferred income taxes   2,755 [1]    
Prepaid expenses and other assets      [1]    
Total current assets 20,419 32,245 [1]    
Oil and natural gas properties and equipment 269,481 270,122 [1]    
Furniture, fixtures and other      [1]    
Total property and equipment 269,481 270,122 [1]    
Less accumulated depreciation, depletion and amortization 111,585 27,310 [1]    
Net property and equipment 157,896 242,812 [1]    
Restricted deposits for asset retirement obligations      [1]    
Deferred income taxes 17,637    [1]    
Other assets 275,181 47,160 [1]    
Total assets 471,133 322,217 [1]    
Accounts payable 2,538 3,020 [1]    
Undistributed oil and natural gas proceeds 341 374 [1]    
Asset retirement obligations      [1]    
Accrued liabilities      [1]    
Income taxes 84,575 20,044 [1]    
Total current liabilities 87,454 23,438 [1]    
Long-term debt      [1]    
Asset retirement obligations, less current portion 27,276 29,725 [1]    
Deferred income taxes      [1]    
Other liabilities      [1]    
Commitments and contingencies       [1]    
Common stock      [1]    
Additional paid-in capital 231,759 236,944 [1]    
Retained earnings 124,644 32,110 [1]    
Treasury stock, at cost      [1]    
Total shareholders' equity 356,403 269,054 [1]    
Total liabilities and shareholders' equity 471,133 322,217 [1]    
Eliminations [Member]
        
Income taxes (74,183) (2,492)    
Total receivables (74,183) (2,492)    
Deferred income taxes   (2,755)    
Total current assets (74,183) (5,247)    
Deferred income taxes (17,637)      
Other assets (631,584) (316,215)    
Total assets (723,404) (321,462)    
Income taxes (74,183) (2,492)    
Total current liabilities (74,183) (2,492)    
Deferred income taxes (17,637) (2,755)    
Other liabilities (275,181) (47,161)    
Commitments and contingencies          
Additional paid-in capital (231,759) (236,944)    
Retained earnings (124,644) (32,110)    
Total shareholders' equity (356,403) (269,054)    
Total liabilities and shareholders' equity $ (723,404) $ (321,462)    
[1] Began operations on May 1, 2010.