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Supplemental Oil And Gas Reserve Information - Unaudited (Tables) | 12 Months Ended
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Dec. 31, 2011
Supplemental Oil And Gas Reserve Information - Unaudited [Abstract] |
Net Proved, Proved Developed And Proved Undeveloped Reserves |
|  |  | September 30, |  |  |  | September 30, |  |  |  | September 30, |
|  | Oil (MBbl) |  |  | Gas (MMcf) |  |  | MBoe |
2009 |  |  |  |  |  |  |  |  |  |  |  |
Proved reserves |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  | 2,193 |  |  |  | 671 |  |  |  | 2,304 |
Revisions of previous estimates |  |  | 781 |  |  |  | (84 | ) |  |  | 767 |
Extensions, discoveries and other additions |  |  | 8,381 |  |  |  | 3,414 |  |  |  | 8,950 |
Sales of reserves in place |  |  | (2 | ) |  |  | (16 | ) |  |  | (5 | )
Purchases of reserves in place |  |  | 1,726 |  |  |  | 1,611 |  |  |  | 1,995 |
Production |  |  | (658 | ) |  |  | (326 | ) |  |  | (712 | )
Net proved reserves at December 31, 2009 |  |  | 12,421 |  |  |  | 5,270 |  |  |  | 13,299 |
Proved developed reserves, December 31, 2009 |  |  | 5,231 |  |  |  | 2,293 |  |  |  | 5,613 |
Proved undeveloped reserves, December 31, 2009 |  |  | 7,190 |  |  |  | 2,977 |  |  |  | 7,686 |
2010 |  |  |  |  |  |  |  |  |  |  |  |
Proved reserves |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  | 12,421 |  |  |  | 5, 270 |  |  |  | 13,299 |
Revisions of previous estimates |  |  | 2,235 |  |  |  | 1,897 |  |  |  | 2,552 |
Extensions, discoveries and other additions |  |  | 22,445 |  |  |  | 12,172 |  |  |  | 24,473 |
Sales of reserves in place |  |  | (122 | ) |  |  | (5 | ) |  |  | (123 | )
Purchases of reserves in place |  |  | 1,363 |  |  |  | 696 |  |  |  | 1,479 |
Production |  |  | (1,792 | ) |  |  | (651 | ) |  |  | (1,900 | )
Net proved reserves at December 31, 2010 |  |  | 36,550 |  |  |  | 19,379 |  |  |  | 39,780 |
Proved developed reserves, December 31, 2010 |  |  | 15,650 |  |  |  | 8,208 |  |  |  | 17,018 |
Proved undeveloped reserves, December 31, 2010 |  |  | 20,900 |  |  |  | 11,171 |  |  |  | 22,762 |
2011 |  |  |  |  |  |  |  |  |  |  |  |
Proved reserves |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  | 36,550 |  |  |  | 19,379 |  |  |  | 39,780 |
Revisions of previous estimates |  |  | (262 | ) |  |  | (159 | ) |  |  | (288 | )
Extensions, discoveries and other additions |  |  | 36,464 |  |  |  | 40,220 |  |  |  | 43,168 |
Sales of reserves in place |  |  | (56 | ) |  |  | (518 | ) |  |  | (142 | )
Purchases of reserves in place |  |  | 100 |  |  |  | 65 |  |  |  | 111 |
Production |  |  | (3,732 | ) |  |  | (1,087 | ) |  |  | (3,914 | )
Net proved reserves at December 31, 2011 |  |  | 69,064 |  |  |  | 57,900 |  |  |  | 78,715 |
Proved developed reserves, December 31, 2011 |  |  | 31,749 |  |  |  | 24,535 |  |  |  | 35,839 |
Proved undeveloped reserves, December 31, 2011 |  |  | 37,315 |  |  |  | 33,365 |  |  |  | 42,876 |
Standardized Measure of Discounted Future Cash Flows |
|  |  | September 30, |  |  |  | September 30, |  |  |  | September 30, |
|  | At Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (In thousands) |
Future cash inflows |  | $ | 6,508,604 |  |  | $ | 2,620,530 |  |  | $ | 664,480 |
Future production costs |  |  | (1,690,264 | ) |  |  | (696,890 | ) |  |  | (258,137 | )
Future development costs |  |  | (783,486 | ) |  |  | (362,328 | ) |  |  | (120,212 | )
Future income tax expense(1) |  |  | (1,225,395 | ) |  |  | (495,788 | ) |  |  | — |
Future net cash flows |  |  | 2,809,459 |  |  |  | 1,065,524 |  |  |  | 286,131 |
10% annual discount for estimated timing of cash flows |  |  | (1,489,988 | ) |  |  | (579,789 | ) |  |  | (152,601 | )
Standardized measure of discounted future net cash flows |  | $ | 1,319,471 |  |  | $ | 485,735 |  |  | $ | 133,530 |
(1) | Does not include the effect of income taxes on discounted future net cash flows for the years ended December 31, 2009 because as of December 31, 2009, the Company was a limited liability company not subject to entity-level taxation. Accordingly, no provision for federal or state corporate income taxes was provided because taxable income was passed through to the Company's equity holders.
Changes In The Standardized Measure Of Discounted Future Net Cash Flows Applicable To Proved Oil And Natural Gas Reserves |
|  |  | September 30, |  |  |  | September 30, |  |  |  | September 30, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (In thousands) |
January 1, |  | $ | 485,735 |  |  | $ | 133,530 |  |  | $ | 17,730 |
Net changes in prices and production costs |  |  | 299,108 |  |  |  | 126,089 |  |  |  | 11,423 |
Net changes in future development costs |  |  | (38,244 | ) |  |  | (9,767 | ) |  |  | 1,998 |
Sales of oil and natural gas, net |  |  | (262,485 | ) |  |  | (100,577 | ) |  |  | (25,254 | )
Extensions |  |  | 989,697 |  |  |  | 426,824 |  |  |  | 71,333 |
Discoveries |  |  | — |  |  |  | — |  |  |  | — |
Purchases of reserves in place |  |  | 2,679 |  |  |  | 26,919 |  |  |  | 36,809 |
Sales of reserves in place |  |  | (2,499 | ) |  |  | (1,720 | ) |  |  | (108 | )
Revisions of previous quantity estimates |  |  | (5,058 | ) |  |  | 55,149 |  |  |  | 7,700 |
Previously estimated development costs incurred |  |  | 146,847 |  |  |  | 32,729 |  |  |  | — |
Accretion of discount |  |  | 69,782 |  |  |  | 13,353 |  |  |  | 3,352 |
Net change in income taxes |  |  | (372,146 | ) |  |  | (212,085 | ) |  |  | — |
Changes in timing and other |  |  | 6,055 |  |  |  | (4,709 | ) |  |  | 8,547 |
December 31, |  | $ | 1,319,471 |  |  | $ | 485,735 |  |  | $ | 133,530 |

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- Definition Tabular disclosure of the net quantities of an enterprise's interests in proved developed and undeveloped reserves of (a) crude oil (including condensate and natural gas liquids), (b) natural gas (including coal bed methane), (c) synthetic oil, (d) synthetic gas, and (e) other nonrenewable natural resources that are intended to be upgraded during the period as of the beginning of the period, changes in quantities during the period, and as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61872-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61831-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59E, 59F, 59G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61884-109447 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61858-109447 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61797-109447 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6821537&loc=d3e61869-109447 + Details
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