Note 6 - Fair Value Measurements (Details) - Gross Realized Gains and Gross Realized Losses (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	$ 10,151	$ 1,334	$ 608
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(7,135)	(3,794)	(1,287)
Net realized gain (loss) on sales of available-for-sale securities	3,016	(2,460)	(679)
Equity Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	7,719	1,251
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(6,183)
Debt Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	2,432	83	608
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	$ (952)	$ (3,794)	$ (1,287)

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- Definition

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.

+ References

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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.

+ References

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