Note 6 - Fair Value Measurements - Gross Realized Gains and Gross Realized Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gross realized gains on sales of available-for-sale securities	$ 2,669	$ 2,271	$ 10,151
Gross realized losses on sales of available-for-sale securities	(1,596)	(3,182)	(7,135)
Net realized gain (loss) on sales of available-for-sale securities	1,073	(911)	3,016
Equity Securities [Member]
Gross realized gains on sales of available-for-sale securities	2,669	1,854	7,719
Gross realized losses on sales of available-for-sale securities	(1,596)	(2,949)	(6,183)
Debt Securities [Member]
Gross realized gains on sales of available-for-sale securities		417	2,432
Gross realized losses on sales of available-for-sale securities		$ (233)	$ (952)

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.

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=73527792&loc=d3e27357-111563

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