Acquisition of Atlantic Rim Working Interests (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Acquisition of Atlantic Rim Working Interest (Textual) [Abstract]
Total fair value of oil and gas properties acquired	$ 4,874
Effective date of transaction of purchase price allocation based on estimated fair value	Aug. 01, 2012

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 805

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