Note 2 - Investments and Restricted Cash (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Note 2 - Investments and Restricted Cash (Details) [Line Items]
Long-term Investments	$ 4,334,000us-gaap_LongTermInvestments	$ 4,920,000us-gaap_LongTermInvestments
Tax Basis of Investments, Cost for Income Tax Purposes	4,900,000	7,300,000
Other than Temporary Impairment Losses, Investments	2,800,000us-gaap_ImpairmentOfInvestments
Payments to Acquire Investments	947,000us-gaap_PaymentsToAcquireInvestments
Restricted Investments	900,000us-gaap_RestrictedInvestments	900,000us-gaap_RestrictedInvestments
Non-Current Investments Held Having Net Loss Position [Member]
Note 2 - Investments and Restricted Cash (Details) [Line Items]
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	$ 600,000

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Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

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- Definition

The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

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- Definition

The aggregate cost of investments for Federal income tax purposes.

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