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Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value	$ 25,349	$ 59,255
Less than Twelve Months, Gross Unrealized Losses	(1,207)	(4,608)
Twelve Months or Greater, Fair Value	34,622	15,092
Twelve Months or Greater, Gross Unrealized Losses	(3,011)	(1,386)
Total, Fair Value	59,971	74,347
Total, Gross Unrealized Losses	(4,218)	(5,994)
Taxable [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value		1,301
Less than Twelve Months, Gross Unrealized Losses		(38)
Total, Fair Value		1,301
Total, Gross Unrealized Losses		(38)
Tax-exempt [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value		26,743
Less than Twelve Months, Gross Unrealized Losses		(2,883)
Twelve Months or Greater, Fair Value		2,678
Twelve Months or Greater, Gross Unrealized Losses		(383)
Total, Fair Value		29,421
Total, Gross Unrealized Losses		(3,267)
US Government Agencies Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value	4,573	13,130
Less than Twelve Months, Gross Unrealized Losses	(247)	(929)
Twelve Months or Greater, Fair Value	12,738	7,166
Twelve Months or Greater, Gross Unrealized Losses	(995)	(732)
Total, Fair Value	17,311	20,295
Total, Gross Unrealized Losses	(1,242)	(1,661)
US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value	7,753
Less than Twelve Months, Gross Unrealized Losses	(561)
Twelve Months or Greater, Fair Value	13,146
Twelve Months or Greater, Gross Unrealized Losses	(1,676)
Total, Fair Value	20,899
Total, Gross Unrealized Losses	(2,237)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Note 6 - Investment Securities Available For Sale (Details) - Gross Unrealized Losses and Fair Value [Line Items]
Less than Twelve Months, Fair Value	13,023	18,082
Less than Twelve Months, Gross Unrealized Losses	(399)	(757)
Twelve Months or Greater, Fair Value	8,738	5,248
Twelve Months or Greater, Gross Unrealized Losses	(340)	(271)
Total, Fair Value	21,761	23,330
Total, Gross Unrealized Losses	$ (739)	$ (1,028)

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Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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