Note 3 - Financial Instruments (Details) - Available-for-sale Securities (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 14,761	$ 2,359
Unrealized Losses	(6)
Fair Value	14,755us-gaap_AvailableForSaleSecurities	2,359us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,510	2,359
Unrealized Losses	(2)
Fair Value	6,508	2,359
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,251
Unrealized Losses	(4)
Fair Value	$ 8,247

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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

-Publisher FASB

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

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