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Suspended Well Costs Suspended Well Costs (Tables) | 12 Months Ended
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Dec. 31, 2016
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 2016, 2015, and 2014. 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,
| 2016 |  | 2015 |  | 2014
| (in thousands)
Beginning balance on January 1, | $ | 11,952 |  |  | $ | 43,589 |  |  | $ | 34,527 |
Additions to capitalized exploratory well costs pending the determination of proved reserves | 19,846 |  |  | 11,952 |  |  | 43,589 |
Divestitures | — |  |  | (809 | ) |  | — |
Reclassifications to wells, facilities, and equipment based on the determination of proved reserves | (11,952 | ) |  | (18,485 | ) |  | (33,340 | )
Capitalized exploratory well costs charged to expense | — |  |  | (24,295 | ) |  | (1,187 | )
Ending balance at December 31, | $ | 19,846 |  |  | $ | 11,952 |  |  | $ | 43,589 |

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- Definition Suspended Well Costs [Abstract] + References No definition available. + Details
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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=68064819&loc=SL6806780-109447 + Details
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