Net income (loss) available to common shareholders $ 1,663  $ (5,853 ) $ 504  $ 1,233  $ 1,895  $ 879  $ 439  $ 291  $ 30  $ 215  $ 454  $ 17  $ (946 ) $ (32 ) $ (183 ) $ 23  $ 12  $ 4  $ (1 )
Earnings per common share – basic:                   
 Income (loss) before cumulative effect of accounting change $ 2.63  $ (9.57 ) $ 0.94  $ 2.70  $ 4.76  $ 2.73  $ 1.73  $ 1.36  $ 0.18  $ 1.33  $ 3.52  $ 0.17  $ (9.97 ) $ (0.45 ) $ (2.79 ) $ 0.43  $ 0.22  $ 0.08  $ (0.02  )
 Cumulative effect of accounting change   —   —   —   —   —   —   —   0.02   —   —   —   —   —   —   —   —   —   —   — 
 EPS – basic $ 2.63  $ (9.57 ) $ 0.94  $ 2.70  $ 4.76  $ 2.73  $ 1.73  $ 1.38  $ 0.18  $ 1.33  $ 3.52  $ 0.17  $ (9.97 ) $ (0.45 ) $ (2.79 ) $ 0.43  $ 0.22  $ 0.08  $ (0.02 )
Earnings per common share – diluted:                   
 Income (loss) before cumulative effect of accounting change $ 2.51  $ (9.57 ) $ 0.93  $ 2.63  $ 4.33  $ 2.51  $ 1.53  $ 1.20  $ 0.17  $ 1.25  $ 3.01  $ 0.16  $ (9.97 ) $ (0.45 ) $ (2.79 ) $ 0.40  $ 0.21  $ 0.08  $ (0.02  )
 Cumulative effect of accounting change   —   —   —   —   —   —   —   0.01   —   —   —   —   —   —   —   —   —   —   — 
 EPS – diluted $ 2.51  $ (9.57 ) $ 0.93  $ 2.63  $ 4.33  $ 2.51  $ 1.53  $ 1.21  $ 0.17  $ 1.25  $ 3.01  $ 0.16  $ (9.97 ) $ (0.45 ) $ (2.79 ) $ 0.40  $ 0.21  $ 0.08  $ (0.02 )
Cash provided by (used in) operating activities (GAAP) $ 5,117  $ 4,356   $ 5,357   $ 4,974  $ 4,843  $ 2,407  $ 1,432  $ 939  $ 429  $ 478  $ 315  $ 145  $ 95  $ 139  $ 84  $ 121  $ 55  $  19  $ (1 )
Operating cash flow (non-GAAP) * $ 4,548  $ 4,333  $ 5,299  $ 4,675  $ 4,040  $ 2,426  $  1,403  $ 897  $ 409  $ 443  $ 306  $ 139  $ 118  $ 68  $ 161  $ 88  $ 46  $ 16  $ 4 
Balance Sheet Data (at end of period)
Total assets $ 37,179  $ 29,914  $ 38,593  $ 30,764  $ 24,413  $ 16,114  $ 8,245  $ 4,572  $ 2,876  $ 2,287  $ 1,440  $ 851  $ 813  $ 953  $ 949  $ 572  $ 277  $ 126  $ 79 
Long-term debt, net of current maturities $  12,640  $ 12,295  $ 13,175  $ 10,178  $ 7,187  $ 5,286  $ 3,075  $ 2,058  $ 1,651  $ 1,329  $ 945  $ 964  $ 919  $ 509  $ 509  $ 268  $ 146  $ 48  $ 14 
Stockholders’ equity (deficit) $ 15,264  $ 12,341  $ 17,017  $ 12,624  $ 11,366  $ 6,299  $ 3,163  $ 1,733  $ 908  $ 767  $ 313  $ (218 ) $ (249 ) $ 280  $ 287  $ 178  $ 45  $ 31  $ 31 
Other Operating and Financial Data
Proved reserves in natural gas equivalents (bcfe)   17,096   14,254   12,051   10,879   8,956   7,521   4,902   3,169   2,205   1,780   1,355   1,206   1,091   448   403   425   243   142   137 
Future net natural gas and oil revenues discounted at 10% ** $ 15,146  $ 9,449  $ 15,601  $ 20,573  $ 13,647  $ 22,934  $ 10,504  $ 7,333  $ 3,718  $ 1,647  $ 6,046  $ 1,089  $ 661  $ 467  $ 437  $ 547  $ 188  $ 141  $ 142 
Natural gas price used in reserve report (per mcf)*** $ 3.52  $ 3.13  $ 5.12  $ 6.19  $ 5.41  $ 8.76  $ 5.65   $ 5.68  $ 4.28  $ 2.51  $ 10.12  $ 2.25  $ 1.68  $ 2.29  $ 2.12  $ 2.41  $ 1.60  $ 1.98  $ 2.43 
Oil price used in reserve report (per bbl)*** $ 75.17   $ 56.72  $ 41.60  $ 90.58  $ 56.25  $ 56.41  $ 39.91   $ 30.22  $ 30.18  $ 18.82  $ 26.41  $ 24.72  $ 10.48  $ 17.62  $ 18.38  $ 20.90  $ 17.41  $ 18.27  $ 18.71 
Natural gas production (bcf)   925   835   775   655   526   422   322   240   161   144   116   109   94   27   62   52   25   7   3 
Oil production (mmbbl)   18.4   11.8   11.2   9.9   8.7   7.7   6.8   4.7   3.5   2.9   3.1   4.1   6.0   1.9   2.8   1.4   1.1   0.5   0.3 
Production (bcfe)   1,035   906   843   714   578   469   363   268   181   161   134   133   130   38   79   60   32   10   4 
Sales price per mcfe**** $ 6.09  $ 6.22  $ 8.38  $ 8.40  $ 8.86  $ 6.90  $ 5.23  $ 4.79   $ 3.61  $ 4.56  $ 3.50  $ 2.10  $ 1.97  $ 2.49  $ 2.45  $ 1.84  $ 1.78  $ 2.21  $ 2.68 
Production expense per mcfe $ 0.86  $ 0.97  $ 1.05  $ 0.90  $ 0.85  $ 0.68  $ 0.56  $ 0.51  $ 0.54  $ 0.47  $ 0.37  $ 0.35   $ 0.39   $ 0.20  $ 0.15  $ 0.11  $ 0.11  $ 0.21  $ 0.67