Oil and Gas Disclosures (Unaudited) - Costs Incurred in Property Acquisition, Exploration and Development (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Acquisition of properties:
Proved		$ 4
Unproved
Exploration
Development	276us-gaap_CostsIncurredDevelopmentCosts	1,359us-gaap_CostsIncurredDevelopmentCosts
Total domestic costs incurred	$ 276	$ 1,363

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Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have proved reserves.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62038-109447

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 18

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62014-109447

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- Definition

Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves.

+ References

+ Details

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- Definition

Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 18

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62014-109447

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- Definition

Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Exploration

-URI http://asc.fasb.org/extlink&oid=6512329

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 18

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62014-109447

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Amount of costs incurred related to oil and gas property acquisition, exploration and development activities, including capitalized costs and costs charged to expense.

+ References

No definition available.

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