Note 6 - Fair Value Measurements (Details) - Aggregate Fair Value of Securities in Unrealized Loss Positions (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2014	Dec. 31, 2013
Note 6 - Fair Value Measurements (Details) - Aggregate Fair Value of Securities in Unrealized Loss Positions [Line Items]
Number of Securities in Loss Position	43	79
Aggregate Loss Position	$ (701)	$ (1,143)
Aggregate Fair Value of Securities in a Loss Position	120,912	60,614
Debt Securities [Member]
Note 6 - Fair Value Measurements (Details) - Aggregate Fair Value of Securities in Unrealized Loss Positions [Line Items]
Number of Securities in Loss Position	40	72
Aggregate Loss Position	(221)	(430)
Aggregate Fair Value of Securities in a Loss Position	12,509	46,440
Equity Securities [Member]
Note 6 - Fair Value Measurements (Details) - Aggregate Fair Value of Securities in Unrealized Loss Positions [Line Items]
Number of Securities in Loss Position	3	7
Aggregate Loss Position	(480)	(713)
Aggregate Fair Value of Securities in a Loss Position	$ 108,403	$ 14,174

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Amount of unrealized loss on securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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