Note 13 - Asset Retirement Obligation (Details) - Reconciliation of the Beginning and Ending Aggregate Carrying Amount of Asset Retirement Obligation (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Reconciliation of the Beginning and Ending Aggregate Carrying Amount of Asset Retirement Obligation [Abstract]
Balance	$ 19,289	$ 21,284
Revisions in estimated cash flows	(2,742)	(3,696)
Liabilities incurred	588
Accretion expense	1,544	1,701
Balance	$ 18,679	$ 19,289

Asset Retirement Obligation, Accretion Expense Accrued

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- Details

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ 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)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

-URI http://asc.fasb.org/extlink&oid=6505190

+ Details

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

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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

+ Details

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