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Note 5 - Investment Securities Available For Sale (Detail) (USD $)	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Available-for-sale Securities Pledged as Collateral	$ 55,600,000		$ 55,800,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	7
Percentage of Portfolio	96.00%
Available-for-sale Securities, Current	179,140,000	193,977,000
Available-for-sale Securities, Gross Unrealized Gains	9,127,000	7,104,000
Available-for-sale Securities, Gross Unrealized Losses	33,000	224,000
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale Securities, Current	5,400,000
Available-for-sale Securities, Gross Unrealized Gains	570,000	411,000
Available-for-sale Securities, Gross Unrealized Losses	$ 2,000	$ 95,000

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No definition available.

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired.

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The fair value of available-for-sale securities that serve as collateral for borrowings.

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