Note 3 - Marketable Equity Securities (Details) - Recognized Gains (Losses) in Market Value for Securities (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Trading securities
Recognized gain (loss)	$ 8	$ (26)	$ (16)
Change in net recognized gain (loss)	138	34	(10)
Recognized gain (loss)	$ 146	$ 8	$ (26)

Amount of increase (decrease) in the fair value of equity or debt securities classified as trading.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3444-108585

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