Note 7 - Asset Retirement Obligation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Apr. 27, 2012
Note 7 - Asset Retirement Obligation (Details) [Line Items]
Asset Retirement Obligation, Revision of Estimate	$ 3,408
Asset Retirement Obligation, Liabilities Settled	(2,093)
Ownership Percentage Sold	49.00%	49.00%
Block Z-1 [Member]
Note 7 - Asset Retirement Obligation (Details) [Line Items]
Asset Retirement Obligation, Liabilities Settled	$ 2,100

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Ownership percentage of Block Z-1 sold under the Stock Purchase Agreement

+ References

No definition available.

+ Details

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

+ Details

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- Definition

Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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