Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due in one year or less, amortized cost	$ 2,305
Investment securities available for sale, due in one year or less, fair value	2,324
Investment securities available for sale, due after one year through five years, amortized cost	72,450
Investment securities available for sale, due after one year through five years, fair value	72,418
Investment securities available for sale, due after five years through ten years, amortized cost	112,719
Investment securities available for sale, due after five years through ten years, fair value	111,348
Investment securities available for sale, due after ten years, amortized cost	25,358
Investment securities available for sale, due after ten years, fair value	25,421
Investment securities available for sale, amortized cost	212,832
Investment securities available for sale, fair value	211,511us-gaap_AvailableForSaleSecurities	214,383us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due after one year through five years, amortized cost	2,015
Investment securities available for sale, due after one year through five years, fair value	2,017
Investment securities available for sale, due after five years through ten years, amortized cost	1,915
Investment securities available for sale, due after five years through ten years, fair value	1,948
Investment securities available for sale, amortized cost	3,930
Investment securities available for sale, fair value	3,965
US States and Political Subdivisions Debt Securities [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due in one year or less, amortized cost	1,898
Investment securities available for sale, due in one year or less, fair value	1,917
Investment securities available for sale, due after one year through five years, amortized cost	2,050
Investment securities available for sale, due after one year through five years, fair value	2,115
Investment securities available for sale, due after five years through ten years, amortized cost	2,717
Investment securities available for sale, due after five years through ten years, fair value	2,700
Investment securities available for sale, amortized cost	6,665
Investment securities available for sale, fair value	6,732	7,460
Collateralized Mortgage Obligations (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due in one year or less, amortized cost	407
Investment securities available for sale, due in one year or less, fair value	407
Investment securities available for sale, due after one year through five years, amortized cost	11,227
Investment securities available for sale, due after one year through five years, fair value	11,041
Investment securities available for sale, due after five years through ten years, amortized cost	77,677
Investment securities available for sale, due after five years through ten years, fair value	76,326
Investment securities available for sale, amortized cost	89,311
Investment securities available for sale, fair value	87,774	93,132
Other Mortgage-Backed (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due after one year through five years, amortized cost	42,042
Investment securities available for sale, due after one year through five years, fair value	42,112
Investment securities available for sale, due after five years through ten years, amortized cost	19,191
Investment securities available for sale, due after five years through ten years, fair value	19,158
Investment securities available for sale, due after ten years, amortized cost	17,299
Investment securities available for sale, due after ten years, fair value	17,233
Investment securities available for sale, amortized cost	78,532
Investment securities available for sale, fair value	78,503	76,020
SBA Loan-Backed (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Amortized Cost and Estimated Fair Value of Investment Securities Available for Sale [Line Items]
Investment securities available for sale, due after one year through five years, amortized cost	15,116
Investment securities available for sale, due after one year through five years, fair value	15,133
Investment securities available for sale, due after five years through ten years, amortized cost	11,219
Investment securities available for sale, due after five years through ten years, fair value	11,216
Investment securities available for sale, due after ten years, amortized cost	8,059
Investment securities available for sale, due after ten years, fair value	8,188
Investment securities available for sale, amortized cost	34,394
Investment securities available for sale, fair value	$ 34,537	$ 37,771

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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-Paragraph 1

-Subparagraph (b)

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the second through fifth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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