Note 13 - Condensed Financial Statements of Parent Company - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operating Expenses
Net income	$ 14,092	$ 14,942	$ 15,833
Adjustment to reconcile net income to net cash provided by operating activities:
Amortization of premiums and accretion of discounts, net	58	89	117
Depreciation	805	801	749
Gain on sale of securities	(14)	(232)	(33)
Loss on disposal of fixed assets	(134)		15
Other assets	(2,537)	438	559
Net change in other liabilities	101	(41)	963
Cash Flows from Investing Activities
Net change in interest-bearing deposits	29,035	50,543	(28,263)
Maturities, sales and calls of securities available for sale	13,812	220,581	64,556
Maturities and calls of securities held to maturity	8,975	16,945	9,205
Cash Flows from Financing Activities
Cash dividends paid	(8,141)	(8,071)	(7,930)
Stock options exercised			173
Net change in cash	(1,048)	1,822	(742)
Parent Company [Member]
Cash Flows from Operating Expenses
Net income	14,092	14,942	15,833
Adjustment to reconcile net income to net cash provided by operating activities:
Equity in undistributed net income of subsidiaries	(6,532)	(5,896)	(8,533)
Amortization of premiums and accretion of discounts, net		1	1
Depreciation	0		3
Gain on sale of securities	(4)
Loss on disposal of fixed assets			2
Net change in refundable income taxes due from subsidiaries	(146)	(223)	106
Other assets	(156)	219	(81)
Net change in other liabilities	(40)	(227)	128
Net cash provided by operating activities	7,214	8,816	7,459
Cash Flows from Investing Activities
Net change in interest-bearing deposits	807	(1,140)	307
Maturities, sales and calls of securities available for sale	192
Maturities and calls of securities held to maturity		450	0
Capital distribution to subsidiary	(100)
Net cash provided by (used in) investing activities	899	(690)	307
Cash Flows from Financing Activities
Cash dividends paid	(8,141)	(8,071)	(7,930)
Stock options exercised	0		173
Net cash used in financing activities	(8,141)	(8,071)	(7,757)
Net change in cash	(28)	55	9
Cash due from subsidiaries at beginning of year	74	19	10
Cash due from subsidiaries at end of year	$ 46	$ 74	$ 19

Represents the amount of capital distribution made to a subsidiary during the period.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.