Note 6 - Fair Value Measurements (Details) - Gross Realized Gains and Gross Realized Losses (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	$ 100	$ 344	$ 7,438	$ 476
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(649)	(1,006)	(1,082)	(1,225)
Net realized gain (loss) on sales of available-for-sale securities	(549)	(662)	6,356	(749)
Equity Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities		216	5,518	216
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	(467)		(709)
Debt Securities [Member]
Gross realized gains on sales of available-for-sale securities
Gross realized gains on sales of available-for-sale securities	100	128	1,920	260
Gross realized losses on sales of available-for-sale securities
Gross realized losses on sales of available-for-sale securities	$ (182)	$ (1,006)	$ (373)	$ (1,225)

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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

+ Details

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- Definition

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

+ Details

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- Definition

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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