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Suspended Well Costs (Tables) | 12 Months Ended
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Dec. 31, 2013
Suspended Well Costs [Abstract] |
Capitalized Exploratory Well Costs, Roll Forward [Table Text Block] | The following table reflects the net changes in capitalized exploratory well costs during 2013, 2012, and 2011. The table does not include amounts that were capitalized and either subsequently expensed or reclassified to producing well costs in the same year:
| For the Years Ended December 31,
| 2013 |  | 2012 |  | 2011
| (in thousands)
Beginning balance on January 1, | $ | 9,100 |  |  | $ | 18,600 |  |  | $ | 35,862 |
Additions to capitalized exploratory well costs pending the determination of proved reserves | 34,527 |  |  | 9,100 |  |  | 15,618 |
Reclassifications to wells, facilities, and equipment based on the determination of proved reserves | (9,100 | ) |  | (5,865 | ) |  | (32,880 | )
Capitalized exploratory well costs charged to expense | — |  |  | (12,735 | ) |  | — |
Ending balance at December 31, | $ | 34,527 |  |  | $ | 9,100 |  |  | $ | 18,600 |
Schedule of Aging of Capitalized Exploratory Well Costs [Table Text Block] | The following table provides an aging of capitalized exploratory well costs based on the date the drilling was completed and the number of projects for which exploratory well costs have been capitalized for more than one year since the completion of drilling:
| As of December 31,
| 2013 |  | 2012 |  | 2011
| (in thousands)
Exploratory well costs capitalized for one year or less | $ | 34,527 |  |  | $ | 9,100 |  |  | $ | 15,618 |
Exploratory well costs capitalized for more than one year | — |  |  | — |  |  | 2,982 |
Ending balance at December 31, | $ | 34,527 |  |  | $ | 9,100 |  |  | $ | 18,600 |
Number of projects with exploratory well costs that have been capitalized more than a year | — |  |  | — |  |  | 2 |

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- Definition Tabular disclosure of the change in capitalized exploratory costs during 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 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=8451039&loc=SL6806780-109447 + Details
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- Definition Tabular disclosure of the amount of exploratory well costs that have been capitalized after the completion of drilling and the number of projects for which those costs relate. Additionally, for exploratory well costs that have been capitalized for periods greater than one year at the most recent balance sheet date, this block of text may be used to disclose an aging of those amounts by year, or by using a range of years, and the number of projects to which those costs relate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=8451039&loc=SL6806780-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS19-1 -Paragraph 10 -Subparagraph b -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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