Note 6 - Fair Value Measurements (Details) - Gross Realized Gains and Gross Realized Losses - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	$ 843	$ 100	$ 1,246	$ 7,438
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(370)	(649)	(784)	(1,082)
Net realized gain (loss) on sales of available-for-sale securities	473	(549)	462	6,356
Equity Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	638		875	5,518
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(232)	(467)	(557)	(709)
Debt Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	205	100	371	1,920
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	$ (138)	$ (182)	$ (227)	$ (373)

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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