CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (loss) [Member]	Total
Balance at Dec. 31, 2017	$ 111,138	$ 2,937	$ 144,197	$ (2,330)	$ 255,942
Balance (in shares) at Dec. 31, 2017	15,223,360
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			21,773		21,773
Other comprehensive loss, net of tax				(8,225)	(8,225)
Exercise of stock options	$ 941	(171)			770
Exercise of stock options (in shares)	54,350
Stock compensation costs		274			274
Stock issued-acquisition		(6)			(6)
Cash dividends			(7,320)		(7,320)
Balance at Sep. 30, 2018	$ 112,079	3,034	158,650	(10,555)	263,208
Balance (in shares) at Sep. 30, 2018	15,277,710
Balance at Jun. 30, 2018	$ 111,739	2,994	154,021	(8,516)	260,238
Balance (in shares) at Jun. 30, 2018	15,258,100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			7,071		7,071
Other comprehensive loss, net of tax				(2,039)	(2,039)
Exercise of stock options	$ 340	(60)			280
Exercise of stock options (in shares)	19,610
Stock compensation costs		100			100
Cash dividends			(2,442)		(2,442)
Balance at Sep. 30, 2018	$ 112,079	3,034	158,650	(10,555)	263,208
Balance (in shares) at Sep. 30, 2018	15,277,710
Balance at Dec. 31, 2018	$ 112,507	3,066	164,117	(6,666)	273,024
Balance (in shares) at Dec. 31, 2018	15,300,460
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			26,676		26,676
Other comprehensive loss, net of tax				12,557	12,557
Exercise of stock options	$ 630	(112)			518
Exercise of stock options (in shares)	38,610
Stock compensation costs		379			379
Stock repurchase	$ (340)		(1,034)		(1,374)
Stock repurchase (in shares)	(54,579)
Cash dividends			(8,427)		(8,427)
Balance at Sep. 30, 2019	$ 112,797	3,333	181,332	5,891	303,353
Balance (in shares) at Sep. 30, 2019	15,284,491
Balance at Jun. 30, 2019	$ 113,061	3,237	176,328	4,226	296,852
Balance (in shares) at Jun. 30, 2019	15,332,550
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			8,952		8,952
Other comprehensive loss, net of tax				1,665	1,665
Exercise of stock options	$ 76	(16)			60
Exercise of stock options (in shares)	6,520
Stock compensation costs		112			112
Stock repurchase	$ (340)		(1,034)		(1,374)
Stock repurchase (in shares)	(54,579)
Cash dividends			(2,914)		(2,914)
Balance at Sep. 30, 2019	$ 112,797	$ 3,333	$ 181,332	$ 5,891	$ 303,353
Balance (in shares) at Sep. 30, 2019	15,284,491