Note 18 - Parent Company Financial Information (Details) - Condensed Statement of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Operating Activities
Net income	$ 8,998us-gaap_NetIncomeLoss	$ 8,392us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Net securities gains	(1,112)us-gaap_GainLossOnInvestments	(824)us-gaap_GainLossOnInvestments
Stock-based compensation expense	83us-gaap_ShareBasedCompensation	71us-gaap_ShareBasedCompensation
Increase in other liabilities	122	(173)
Decrease in other assets	(100)	4,140
Deferred income tax provision	(368)	(212)
Net cash provided by operating activities	5,977	17,323
Investing activities
Purchase of investment securities	(92,017)	(130,213)
Proceeds from sale of investment securities	29,972	19,559
Net cash used by investing activities	(33,440)	(29,172)
Financing activities
Cash dividend paid	(3,328)us-gaap_PaymentsOfDividendsCommonStock	(3,130)us-gaap_PaymentsOfDividendsCommonStock
Proceeds from issuance of common stock	628	535
Tax benefit from exercise of stock options	29	2
Net cash used by financing activities	29,422	12,682
Increase (decrease) in cash and cash equivalents	1,959	833
Cash and cash equivalents at beginning of year	16,286	15,453
Cash and cash equivalents at end of year	18,245	16,286
Parent Company [Member]
Operating Activities
Net income	8,998	8,392
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed income from subsidiary	(5,491)	(4,588)
Net securities gains	(1,045)	(629)
Stock-based compensation expense	83	71
Increase in other liabilities	225
Decrease in other assets	12	443
Deferred income tax provision	29
Net cash provided by operating activities	2,811	3,689
Investing activities
Purchase of investment securities	(4,955)	(3,763)
Proceeds from sale of investment securities	4,839	2,589
Net cash used by investing activities	(116)	(1,174)
Financing activities
Cash dividend paid	(3,328)	(3,130)
Proceeds from issuance of common stock	628	535
Tax benefit from exercise of stock options	29	2
Net cash used by financing activities	(2,671)	(2,593)
Increase (decrease) in cash and cash equivalents	24	(78)
Cash and cash equivalents at beginning of year	24	102
Cash and cash equivalents at end of year	$ 48	$ 24

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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