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

Capitalized exploratory well costs that were expensed during the year because proved reserves were not found at the exploratory well.

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

Name:	us-gaap_CapitalizedExploratoryWellCostChargedToExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration