Percentage of assets sold (Details)	12 Months Ended
Dec. 31, 2014
Discontinued operations, disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percent of oil and natural gas production sold	93.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
Period Type:	duration