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Suspended Well Costs (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2015
Suspended Well Costs [Abstract] |
Capitalized Exploratory Well Cost, Charged to Expense | $ 15.1 us-gaap_CapitalizedExploratoryWellCostChargedToExpense

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- Details
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- Definition Capitalized exploratory well costs that were expensed during the year because proved reserves were not found at the exploratory well. + 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)(3) -URI http://asc.fasb.org/extlink&oid=8451039&loc=SL6806780-109447 + Details
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