Note 7 - Investment Securities (Details) - Amortized Cost and Estimated Fair Values of Investment Securities Held-to-Maturity (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Note 7 - Investment Securities (Details) - Amortized Cost and Estimated Fair Values of Investment Securities Held-to-Maturity [Line Items]
State and municipal securities	$ 146	$ 146
State and municipal securities	163	166
State and Municipal [Member]
Note 7 - Investment Securities (Details) - Amortized Cost and Estimated Fair Values of Investment Securities Held-to-Maturity [Line Items]
State and municipal securities	146	146
State and municipal securities	17	20
State and municipal securities	163	166
State and municipal securities	$ 0	$ 0

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of unrecognized gain before loss on investments in held-to-maturity securities.

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Amount of unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI).

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