Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities (Auction Rate Securities [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Auction Rate Securities [Member]
Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities [Line Items]
Cost Basis Amount	$ 7,425	$ 7,425
Gross Unrealized Loss In Accumulated OCI	520	520
Fair Value	$ 6,905	$ 6,905

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

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

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