Note 4 - Inventory (Details) - Inventory (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Inventory [Abstract]
Tubular goods, accessories and spare parts	$ 18,709	$ 18,343
Crude oil	1,360	1,508
Inventory	$ 20,069	$ 19,851
Crude oil (barrels) (in Dollars per Barrel (of Oil))	17,020	17,876
Crude oil (cost per barrel) (in Dollars per Barrel (of Oil))	79.93	84.34

Crude oil barrels included in inventory.

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- Details

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- Definition

Production costs incurred in lifting the oil and gas to the surface during the reporting period divided by the number of barrels of oil equivalents (BOE) produced. Production (or lifting costs) are costs incurred in lifting the oil and gas to the surface and generally include gathering, treating, primary processing, field storage, property taxes and insurance on proved properties, but do not include depreciation, depletion, accretion, amortization, royalties, income taxes, interest, general and administrative and other expenses.

+ References

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 3

-Subparagraph A

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- Definition

Carrying amount as of the balance sheet date of petroleum or crude oil.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section 35

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6386567&loc=d3e3927-108312

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 1

-Subparagraph (b)

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(4),(5))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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