Note 6 - Goodwill and Other Assets (Details) - Summary of Other Assets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Summary of Other Assets [Abstract]
Customer relationships	$ 3,490	$ 3,490
Less: accumulated amortization of intangibles	(3,255)	(3,164)
Net intangible assets	235us-gaap_FiniteLivedIntangibleAssetsNet	326us-gaap_FiniteLivedIntangibleAssetsNet
Investment in TEL	12,192us-gaap_EquityMethodInvestments	8,737us-gaap_EquityMethodInvestments
Other long-term receivables	575us-gaap_OtherReceivables	631us-gaap_OtherReceivables
Deposits	546us-gaap_DepositsAssetsNoncurrent	732us-gaap_DepositsAssetsNoncurrent
Deferred loan costs, net	724us-gaap_UnamortizedDebtIssuanceExpense	931us-gaap_UnamortizedDebtIssuanceExpense
Hedge derivative asset		1,412us-gaap_HedgingAssetsNoncurrent
Other, net	491us-gaap_OtherAssetsMiscellaneous	595us-gaap_OtherAssetsMiscellaneous
	$ 14,763us-gaap_OtherAssetsNoncurrent	$ 13,364us-gaap_OtherAssetsNoncurrent

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

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-Publisher FASB

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-SubTopic 10

-Section S99

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Subparagraph (SX 210.5-02.12)

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Carrying amount as of the balance sheet date of the asset arising from a financial instrument or a contract used to hedge price changes in underlying assets, and which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer.

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Amount of other miscellaneous assets.

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No definition available.

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Carrying amounts due as of the balance sheet date from parties or arising from transactions not otherwise specified in the taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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