Annual report pursuant to Section 13 and 15(d)

Acquisitions and Divestitures - Additional Information (Detail)

v2.4.0.6
Acquisitions and Divestitures - Additional Information (Detail) (USD $)
3 Months Ended 12 Months Ended 1 Months Ended 3 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 1 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
May 15, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2012
Yellow Rose Properties And Fairway Properties
Dec. 31, 2011
Yellow Rose Properties And Fairway Properties
Dec. 31, 2010
Yellow Rose Properties And Fairway Properties
Oct. 05, 2012
Newfield Properties
acre
Dec. 31, 2012
Newfield Properties
Dec. 31, 2012
Newfield Properties
Dec. 31, 2011
Newfield Properties
Oct. 05, 2012
Newfield Properties
8.50% Senior Notes
Oct. 05, 2012
Newfield Properties
Overriding Royalty Interests
Dec. 31, 2010
Tahoe Properties
Nov. 04, 2010
Tahoe Properties
May 11, 2011
Yellow Rose Properties
acre
Apr. 30, 2010
Total Properties
Apr. 30, 2010
Total Properties
Matterhorn
Apr. 30, 2010
Total Properties
Virgo Field
Nov. 04, 2010
Shell
Nov. 04, 2010
Shell
Tahoe field (Viosca Knoll 784)
Nov. 04, 2010
Shell
Southeast Tahoe field (Viosca Knoll 784)
Nov. 04, 2010
Shell
Droshky field (Green Canyon 244)
Aug. 10, 2011
Fairway Properties
Business Acquisition [Line Items]                                                                
Total cash paid for acquisition                               $ 205,550,000             $ 116,233,000 $ 394,377,000 $ 115,012,000     $ 116,200,000       $ 42,870,000
Number of federal offshore blocks                               78                       3        
Leasehold interest acres acquired, gross                               416,000               24,500                
Leasehold interest acres acquired, net                               268,000               21,900                
Number of deep water federal offshore blocks                               65         3                      
Number of productive deep water federal offshore blocks                               6         2                      
Number of conventional shelf blocks                               10                                
Number of producing conventional shelf blocks                               4                                
Issuance of senior notes                                       300,000,000                        
Business acquisition general administrative expenses                           1,600,000   600,000 600,000 600,000       500,000                    
Revenue 237,146,000 185,946,000 215,513,000 235,886,000 261,899,000 245,371,000 252,922,000 210,855,000 874,491,000   971,047,000 705,783,000   64,000,000     29,600,000         97,200,000                    
Direct operating expenses                           25,500,000     5,400,000         19,900,000                    
Depreciation, depletion and amortization                 336,177,000   299,015,000 268,415,000   20,500,000     11,900,000         27,900,000                    
Income taxes                 47,547,000   91,517,000 11,901,000   6,300,000     4,300,000         17,300,000                    
Net income 16,670,000 (1,471,000) 53,567,000 3,218,000 46,065,000 52,928,000 55,175,000 18,649,000 71,984,000   172,817,000 117,892,000   11,700,000     8,000,000         32,100,000                    
Business acquisition, incremental revenue adjustments                           52,400,000 79,200,000     105,700,000 216,800,000     112,400,000                    
Business acquisition, incremental operating costs                           16,400,000 25,300,000     33,200,000 24,600,000     25,300,000                    
Business acquisition, incremental insurance costs estimation                                   600,000                            
Purchase Price Allocation of Unevaluated Properties for Oil and Gag Interests 123,503,000       154,516,000       123,503,000   154,516,000   81,200,000       13,100,000 13,100,000                            
Business acquisition, incremental depreciation depletion amortization and accretion                           21,900,000 50,400,000     53,400,000 102,700,000     39,600,000                    
Assumed borrowings 1,087,611,000       717,000,000       1,087,611,000   717,000,000           205,600,000 205,600,000                            
Effective interest rate                                 7.70% 7.70%                            
Business acquisition, incremental interest expense estimation                           4,600,000 12,900,000     12,000,000 15,800,000                          
Business acquisition, incremental capitalized interest estimation                           1,100,000 3,000,000     600,000 900,000                          
Federal statutory income tax rate                 35.00%   35.00% 35.00% 35.00%         35.00%       35.00%                    
Business acquisition, incremental income tax expense estimation                           4,300,000 2,200,000     2,700,000 25,900,000     16,400,000                    
Percentage of working interest include in producing interest                                                   100.00% 64.00%   70.00% 100.00%   64.30%
Business acquisition debt instrument, interest rate, minimum                         3.10%                                      
Business acquisition debt instrument, interest rate, maximum                         3.50%                                      
Percentage of Royalty Interest                                                             6.25%  
Business acquisition, estimated decrease in interest income                                           1,100,000                    
Percentage of non-operating working interest sold                   40.00%                                            
Proceeds from sale of non-operating working interest                   30,500,000                                            
Reversal of asset retirement obligation                   $ 4,000,000