Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities (Auction Rate Securities [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities [Line Items]
Investment in auction rate securities, cost basis	$ 7,575	$ 7,575
Fair Value, Inputs, Level 1 [Member]
Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities [Line Items]
Investment in auction rate securities, fair value
Fair Value, Inputs, Level 2 [Member]
Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities [Line Items]
Investment in auction rate securities, fair value
Fair Value, Inputs, Level 3 [Member]
Note 6 - Financial Instruments and Fair Value (Details) - Investment in Auction Rate Securities [Line Items]
Investment in auction rate securities, fair value	$ 6,628	$ 6,628