Note 4 - Investment Securities (Details) - Gross Realized Losses on Equity and Debt Securities (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Note 4 - Investment Securities (Details) - Gross Realized Losses on Equity and Debt Securities [Line Items]
Gross realized gains	$ 1,361	$ 868
Gross realized losses	(249)	(1)
Other-than-temporary impairment losses		(43)us-gaap_ImpairmentOfInvestments
Net gains	1,112	824
Equity Securities [Member]
Note 4 - Investment Securities (Details) - Gross Realized Losses on Equity and Debt Securities [Line Items]
Gross realized gains	1,051	672
Gross realized losses	(6)
Other-than-temporary impairment losses		(43)
Net gains	1,045	629
Debt Securities [Member]
Note 4 - Investment Securities (Details) - Gross Realized Losses on Equity and Debt Securities [Line Items]
Gross realized gains	310	196
Gross realized losses	(243)	(1)
Net gains	$ 67	$ 195

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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.

+ 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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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

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