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Note 2 - Derivative Instruments and Hedging Activities (Details) - Outstanding Commodity Forward Contracts (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended	9 Months Ended
	Sep. 30, 2014 Commodity Forward Contract Two [Member]	Sep. 30, 2014 Commodity Forward Contract Three [Member]	Dec. 31, 2013 Commodity Forward Contract One [Member]	Sep. 30, 2013 Commodity Forward Contract Four [Member]	Sep. 30, 2013 Commodity Forward Contract Five [Member]	Sep. 30, 2013 Commodity Forward Contract Six [Member]	Sep. 30, 2013 Commodity Forward Contract Seven [Member]
Note 2 - Derivative Instruments and Hedging Activities (Details) - Outstanding Commodity Forward Contracts [Line Items]
Trade date	Jan. 31, 2014	Mar. 11, 2014	Jun. 21, 2013	Feb. 26, 2013	Mar. 01, 2013	Apr. 15, 2013	Jun. 21, 2013
Effective date	Feb. 01, 2014	Apr. 01, 2014	Oct. 01, 2013	Mar. 01, 2013	Mar. 01, 2013	May 01, 2013	Oct. 01, 2013
Notional amount	$ 3,879	$ 3,014	$ 2,169	$ 2,677	$ 2,636	$ 4,033	$ 2,169
Termination date	Dec. 31, 2014	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Jun. 30, 2014

X

- Definition

Date the derivative contract become effective, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Details

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X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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X

- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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X

- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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