CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Impact of adoption of ASC 326	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Impact of adoption of ASC 326	Treasury Stock	Accumulated Other Comprehensive (Loss) Income
Beginning balance at Dec. 31, 2018	$ 244,583		$ 12,835	$ 185,174	$ 80,088		$ (24,352)	$ (9,162)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	11,380				11,380
Other comprehensive income	6,536							6,536
Exercise of stock options	481		20	461
Purchase of treasury stock	(9,197)						(9,197)
Restricted stock grants			31	(31)
Stock based compensation	314			314
Dividends: Common Stock	(3,976)				(3,976)
Ending balance at Jun. 30, 2019	250,121		12,886	185,918	87,492		(33,549)	(2,626)
Beginning balance at Mar. 31, 2019	250,310		12,885	185,742	83,417		(26,567)	(5,167)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	6,043				6,043
Other comprehensive income	2,541							2,541
Exercise of stock options			1	(1)
Purchase of treasury stock	(6,982)						(6,982)
Stock based compensation	177			177
Dividends: Common Stock	(1,968)				(1,968)
Ending balance at Jun. 30, 2019	250,121		12,886	185,918	87,492		(33,549)	(2,626)
Beginning balance at Dec. 31, 2019	261,551	$ (3,593)	12,905	186,692	98,239	$ (3,593)	(34,492)	(1,793)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	7,353				7,353
Other comprehensive income	10,868							10,868
Exercise of stock options	72		3	69
Purchase of treasury stock	(13,477)						(13,477)
Stock based compensation	312			312
Dividends: Common Stock	(4,211)				(4,211)
Ending balance at Jun. 30, 2020	258,875		12,908	187,073	97,788		(47,969)	9,075
Beginning balance at Mar. 31, 2020	253,646		12,908	186,916	98,805		(45,309)	326
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	1,075				1,075
Other comprehensive income	8,749							8,749
Purchase of treasury stock	(2,660)						(2,660)
Stock based compensation	157			157
Dividends: Common Stock	(2,092)				(2,092)
Ending balance at Jun. 30, 2020	$ 258,875		$ 12,908	$ 187,073	$ 97,788		$ (47,969)	$ 9,075