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Supplemental Information On Oil And Gas Exploration And Production Activities (Tables) | 12 Months Ended
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Dec. 31, 2012
Oil and Gas Exploration and Production Industries Disclosures [Abstract] |
Capitalized Costs Related To Oil And Gas Producing Activities | Capitalized Costs Related to Oil and Gas Producing Activities
| 2012 |  | 2011
Proven properties | $ | 984,795,000 |  |  | $ | 897,130,000 |
Unproven properties | 626,295,000 |  |  | 132,912,000 |
| 1,611,090,000 |  |  | 1,030,042,000 |
Accumulated depreciation, depletion, amortization and impairment reserve | (661,442,000 | ) |  | (571,213,000 | )
Net capitalized costs | $ | 949,648,000 |  |  | $ | 458,829,000 |
Costs Incurred In Oil And Gas Property Acquisition And Development Activities | Costs Incurred in Oil and Gas Property Acquisition and Development Activities
| 2012 |  | 2011 |  | 2010
Acquisition | $ | 513,904,000 |  |  | $ | 119,522,000 |  |  | $ | 17,627,000 |
Development of proved undeveloped properties | 121,787,000 |  |  | 123,489,000 |  |  | 64,652,000 |
Exploratory | 93,397,000 |  |  | 3,994,000 |  |  | — |
Recompletions | 24,643,000 |  |  | 17,259,000 |  |  | 16,917,000 |
Capitalized asset retirement obligation | 2,195,000 |  |  | 1,390,000 |  |  | 1,328,000 |
Total | $ | 755,926,000 |  |  | $ | 265,654,000 |  |  | $ | 100,524,000 |
Results Of Operations For Producing Activities | The results of operations exclude general office overhead and interest expense attributable to oil and gas production.
| 2012 |  | 2011 |  | 2010
Revenues | $ | 248,601,000 |  |  | $ | 228,953,000 |  |  | $ | 127,636,000 |
Production costs | (53,708,000 | ) |  | (47,230,000 | ) |  | (31,580,000 | )
Depletion | (90,230,000 | ) |  | (61,965,000 | ) |  | (38,600,000 | )
| 104,663,000 |  |  | 119,758,000 |  |  | 57,456,000 |
Income tax expense (benefit) |  |  |  |  |
Current | 730,000 |  |  | 282,000 |  |  | 40,000 |
Deferred | 25,633,000 |  |  | (372,000 | ) |  | — |
| 26,363,000 |  |  | (90,000 | ) |  | 40,000 |
Results of operations from producing activities | $ | 78,300,000 |  |  | $ | 119,848,000 |  |  | $ | 57,416,000 |
Depletion per barrel of oil equivalent (BOE) | $ | 35.07 |  |  | $ | 26.56 |  |  | $ | 19.54 |
Oil And Gas Reserves |
| 2012 |  | 2011 |  | 2010
| Oil |  | Gas |  | Oil |  | Gas |  | Oil |  | Gas
| (MBbls) |  | (MMcf) |  | (MBbls) |  | (MMcf) |  | (MBbls) |  | (MMcf)
Proved Reserves |  |  |  |  |  |  |  |  |  |  |
Beginning of the period | 16,745 |  |  | 15,728 |  |  | 19,704 |  |  | 16,158 |  |  | 17,488 |  |  | 14,332 |
Purchases in oil and gas reserves in place | — |  |  | — |  |  | 2 |  |  | 19 |  |  | 3,913 |  |  | 3,482 |
Extensions and discoveries | 4,880 |  |  | 31,265 |  |  | 3,940 |  |  | 2,091 |  |  | 5,574 |  |  | 5,303 |
Sales of oil and gas reserves in place | (10,604 | ) |  | (11,757 | ) |  | — |  |  | — |  |  | — |  |  | — |
Revisions of prior reserve estimates | (382 | ) |  | (357 | ) |  | (4,714 | ) |  | (1,662 | ) |  | (5,426 | ) |  | (6,171 | )
Current production | (2,388 | ) |  | (1,108 | ) |  | (2,187 | ) |  | (878 | ) |  | (1,845 | ) |  | (788 | )
End of period | 8,251 |  |  | 33,771 |  |  | 16,745 |  |  | 15,728 |  |  | 19,704 |  |  | 16,158 |
Proved developed reserves | 5,219 |  |  | 18,482 |  |  | 7,485 |  |  | 6,152 |  |  | 7,230 |  |  | 6,068 |
Proved undeveloped reserves | 3,032 |  |  | 15,289 |  |  | 9,260 |  |  | 9,576 |  |  | 12,474 |  |  | 10,090 |
Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves (Unaudited) | Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves (Unaudited)
| Year ended December 31,
| 2012 |  | 2011 |  | 2010
Future cash flows | $ | 954,833,000 |  |  | $ | 1,594,050,000 |  |  | $ | 1,479,295,000 |
Future development and abandonment costs | (159,113,000 | ) |  | (306,810,000 | ) |  | (301,651,000 | )
Future production costs | (147,024,000 | ) |  | (295,383,000 | ) |  | (305,814,000 | )
Future production taxes | (89,175,000 | ) |  | (124,739,000 | ) |  | (136,323,000 | )
Future income taxes | (114,867,000 | ) |  | (229,649,000 | ) |  | (159,171,000 | )
Future net cash flows | 444,654,000 |  |  | 637,469,000 |  |  | 576,336,000 |
10% discount to reflect timing of cash flows | (96,013,000 | ) |  | (260,788,000 | ) |  | (260,849,000 | )
Standardized measure of discounted future net cash flows | $ | 348,641,000 |  |  | $ | 376,681,000 |  |  | $ | 315,487,000 |
Changes In Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves | Changes in Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves (Unaudited)
| Year ended December 31,
| 2012 |  | 2011 |  | 2010
Sales and transfers of oil and gas produced, net of production costs | $ | (194,893,000 | ) |  | $ | (181,723,000 | ) |  | $ | (96,056,000 | )
Net changes in prices, production costs, and development costs | 108,941,000 |  |  | 136,071,000 |  |  | 122,147,000 |
Acquisition of oil and gas reserves in place | — |  |  | 72,000 |  |  | 63,043,000 |
Extensions and discoveries | 151,654,000 |  |  | 107,110,000 |  |  | 88,227,000 |
Revisions of previous quantity estimates, less related production costs | (10,504,000 | ) |  | (112,553,000 | ) |  | (89,155,000 | )
Sales of reserves in place | (214,867,000 | ) |  | — |  |  | — |
Accretion of discount | 37,668,000 |  |  | 31,549,000 |  |  | 24,077,000 |
Net changes in income taxes | 25,585,000 |  |  | (36,674,000 | ) |  | (54,879,000 | )
Change in production rates and other | 68,376,000 |  |  | 117,342,000 |  |  | 17,309,000 |
Total change in standardized measure of discounted future net cash flows | $ | (28,040,000 | ) |  | $ | 61,194,000 |  |  | $ | 74,713,000 |

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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 4 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61797-109447 Reference 2: 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=8451039&loc=d3e61872-109447 Reference 3: 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=8451039&loc=d3e61858-109447 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=8451039&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 7 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61869-109447 Reference 6: 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=8451039&loc=d3e61831-109447 Reference 7: 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. + Details
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- Definition Tabular disclosure of the future net cash flows relating to proved oil and gas reserves and oil and gas subject to purchase under long-term agreements in which the enterprise participates in the operation of the properties on which the oil and gas is located or otherwise serves as the producer. This information is presented in aggregate and for each geographic area for which reserve quantities are disclosed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62455-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62500-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 36 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62536-109447 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62476-109447 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62424-109447 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62479-109447 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y, 59Z, 59AA, 59BB, 59CC -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. + Details
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