Note 19 - Condensed Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Activities
Net income	$ 4,151	$ 3,778	$ 3,934	$ 220	$ 2,745	$ 3,090	$ 3,143	$ 3,379	$ 12,083	$ 12,357	$ 11,335
Adjustments to reconcile net income to net cash provided by operating activities:
Net unrealized loss (gain) on investment equity securities									47	(770)	336
Stock-based compensation expense									112	118	117
Accretion of discounts on investment securities									2,473	1,501	1,434
Increase (decrease) in other liabilities									(1,531)	(44)	601
Decrease increase (decrease) in other assets									525	423	73
Deferred income tax (benefit) provision									(59)	319	258
Net cash provided by operating activities									7,601	13,898	16,651
Investing activities
Purchase of investment equity securities									(7,914)	(9,030)	(9,763)
Purchase of investment securities available-for-sale									(295,734)	(113,688)	(26,473)
Proceeds from sale of investment equity securities									4,767	11,838	4,902
Proceeds from sale of investment securities available-for-sale									6,930	47,851	4,159
Net cash used in investing activities									(185,133)	(33,574)	(33,111)
Financing activities
Cash dividend paid									(4,226)	(4,086)	(3,863)
Treasury stock purchase									(130)
Proceeds from issuance of common stock									497	591	684
Net cash provided by financing activities									199,255	23,826	13,587
Increase (decrease) in cash and cash equivalents									21,723	4,150	(2,873)
Cash and cash equivalents at beginning of year				17,608				13,458	17,608	13,458	16,331
Cash and cash equivalents at end of period	39,331				17,608				39,331	17,608	13,458
Parent Company [Member]
Operating Activities
Net income									12,083	12,357	11,335
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed income from subsidiary									(7,340)	(6,828)	(7,714)
Net securities (gains) losses									(585)	(1,781)	79
Net unrealized loss (gain) on investment equity securities									47	(770)	336
Stock-based compensation expense									112	118	117
Accretion of discounts on investment securities										(45)
Increase (decrease) in other liabilities									(682)	762	(403)
Decrease increase (decrease) in other assets									17	126	(147)
Deferred income tax (benefit) provision									(20)	247	(158)
Net cash provided by operating activities									3,632	4,186	3,445
Investing activities
Purchase of investment equity securities									(7,914)	(9,030)	(9,763)
Purchase of investment securities available-for-sale										(8,730)
Proceeds from sale of investment equity securities									4,767	11,838	4,902
Proceeds from sale of investment securities available-for-sale										8,775
Net cash used in investing activities									(3,147)	2,853	(4,861)
Financing activities
Cash dividend paid									(4,226)	(4,086)	(3,863)
Treasury stock purchase									(130)
Proceeds from issuance of common stock									497	591	684
Net cash provided by financing activities									(3,859)	(3,495)	(3,179)
Increase (decrease) in cash and cash equivalents									(3,374)	3,544	(4,595)
Cash and cash equivalents at beginning of year				$ 3,616				$ 72	3,616	72	4,667
Cash and cash equivalents at end of period	$ 242				$ 3,616				$ 242	$ 3,616	$ 72