CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Surplus [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at Dec. 31, 2015	$ 275,676	$ 13,717	$ 213,203	$ (8,988)	$ 58,123	$ (379)
Net income	26,477				26,477
Other comprehensive income (loss)	(1,152)					(1,152)
Restricted stock awards forfeitures		(10)	10
Restricted stock units/awards repurchased on vesting to pay taxes	(554)	(24)	(530)
Amortization of restricted stock awards/units	2,836		2,836
Cash dividends declared on common stock	(3,296)				(3,296)
Common stock option expense	56		56
Common stock options exercised and related tax benefits	1,069	59	1,010
Sales of shares (dividend reinvestment program)	22,461	948	21,513
Issuance of shares for Employee Stock Purchase Plan	637	27	610
Balance at Dec. 31, 2016	324,210	14,717	238,708	(8,988)	81,304	(1,531)
Net income	36,497				36,497
Other comprehensive income (loss)	534					534
Restricted stock units issued		62	(62)
Restricted stock awards forfeitures		(1)	1
Restricted stock units/awards repurchased on vesting to pay taxes	(1,826)	(49)	(1,777)
Amortization of restricted stock awards/units	3,741		3,741
Cash dividends declared on common stock	(3,548)				(3,548)
Common stock option expense	6		6
Common stock options exercised and related tax benefits	690	42	648
Sales of shares (dividend reinvestment program)	36,588	1,004	35,584
Issuance of shares for Employee Stock Purchase Plan	797	21	776
Issuance of shares for Employee’s Savings and Investment plan	889	25	864
Issuance of common stock for acquisition	1,500	37	1,463
Issuance of stock offering net of costs	3,600		3,600
Reclassification of certain deferred tax effects					215	(215)
Balance at Dec. 31, 2017	403,678	15,858	283,552	(8,988)	114,468	(1,212)
Net income	44,170				44,170
Other comprehensive income (loss)	(1,260)					(1,260)
Cumulative effect adjustment for adoption of ASU 2016-01					(127)	127
Restricted stock units issued		76	(76)
Restricted stock awards forfeitures		(78)	78
Restricted stock units/awards repurchased on vesting to pay taxes	(1,540)	(38)	(1,502)
Amortization of restricted stock awards/units	4,445		4,445
Cash dividends declared on common stock	(3,712)				(3,712)
Common stock options exercised and related tax benefits	275	19	256
Sales of shares (dividend reinvestment program)	16,677	452	16,225
Issuance of shares for Employee Stock Purchase Plan	958	24	934
Issuance of shares for Employee’s Savings and Investment plan	1,039	29	1,010
Issuance of common stock for acquisition	4,283	117	4,166
Balance at Dec. 31, 2018	$ 469,013	$ 16,459	$ 309,088	$ (8,988)	$ 154,799	$ (2,345)