Financial Instruments, Fair Value Measurements and Credit Risk - Narrative (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	0 Months Ended
Sep. 30, 2014	Sep. 30, 2014 Colombia [Member] Sales Revenue, Segment [Member] Geographic Concentration Risk [Member]	Sep. 30, 2013 Colombia [Member] Sales Revenue, Segment [Member] Geographic Concentration Risk [Member]	Oct. 08, 2012 Block-Brazil [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Participating interest percentage oil and gas property, remaining percentage				30.00%
Concentration risk, percentage		95.00%	96.00%
Foreign exchange losses, Colombian peso to U.S. dollar	$ 80

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13537-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13531-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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