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Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	$ 156,527,000	$ 160,532,000
Gross Unrealized Gains	3,631,000	2,605,000
Gross Unrealized Losses	(4,218,000)	(5,994,000)
Fair Value	155,940,000	157,143,000
Taxable [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	2,958,000	3,787,000
Gross Unrealized Gains	107,000	46,000
Gross Unrealized Losses	(4,000)	(38,000)
Fair Value	3,061,000	3,795,000
Tax-exempt [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	85,147,000	86,524,000
Gross Unrealized Gains	2,384,000	1,562,000
Gross Unrealized Losses	(2,233,000)	(3,267,000)
Fair Value	85,298,000	84,819,000
US Government Agencies Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	26,938,000	27,289,000
Gross Unrealized Gains	209,000	135,000
Gross Unrealized Losses	(1,242,000)	(1,661,000)
Fair Value	25,905,000	25,763,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	37,562,000	38,816,000
Gross Unrealized Gains	621,000	535,000
Gross Unrealized Losses	(739,000)	(1,028,000)
Fair Value	37,444,000	38,323,000
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	3,172,000	3,366,000
Gross Unrealized Gains	304,000	327,000
Fair Value	3,476,000	3,693,000
Debt Securities [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	155,777,000	159,782,000
Gross Unrealized Gains	3,625,000	2,605,000
Gross Unrealized Losses	(4,218,000)	(5,994,000)
Fair Value	155,184,000	156,393,000
Equity Securities in Financial Institutions [Member]
Note 6 - Investment Securities Available For Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	750,000	750,000
Gross Unrealized Gains	6,000
Fair Value	$ 756,000	$ 750,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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