Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Restricted Stock	Restricted Stock Treasury Stock
Beginning balance at Dec. 31, 2017	$ 243,910	$ 97,042	$ 148,298	$ (1,087)	$ (343)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	15,538		15,538
Other comprehensive income (loss)	(5,005)				(5,005)
Forfeiture of restricted stock award grants	(3)	1		(4)
Restricted stock award grants	0	(933)		933
Stock-based compensation expense	949	949
Purchase of treasury stock	(286)			(286)		$ (164)	$ (164)
Cash dividends declared	(5,046)		(5,046)
Ending balance at Jun. 30, 2018	249,893	97,059	158,790	(608)	(5,348)
Beginning balance at Mar. 31, 2018	244,811	96,786	152,872	(602)	(4,245)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	8,441		8,441
Other comprehensive income (loss)	(1,103)				(1,103)
Forfeiture of restricted stock award grants	(3)	1		(4)
Stock-based compensation expense	272	272
Purchase of treasury stock						(2)	(2)
Cash dividends declared	(2,523)		(2,523)
Ending balance at Jun. 30, 2018	249,893	97,059	158,790	(608)	(5,348)
Beginning balance at Dec. 31, 2018	262,830	97,602	171,780	(2,556)	(3,996)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	19,240		19,240
Other comprehensive income (loss)	10,094				10,094
Restricted stock award grants	0	(1,055)		1,055
Stock-based compensation expense	867	867
Purchase of treasury stock	(994)			(994)		(240)	(240)
Cash dividends declared	(5,182)		(5,182)
Ending balance at Jun. 30, 2019	286,615	97,414	185,838	(2,735)	6,098
Beginning balance at Mar. 31, 2019	274,959	97,139	178,662	(1,702)	860
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,767		9,767
Other comprehensive income (loss)	5,238				5,238
Stock-based compensation expense	275	275
Purchase of treasury stock	(994)			(994)		$ (39)	$ (39)
Cash dividends declared	(2,591)		(2,591)
Ending balance at Jun. 30, 2019	$ 286,615	$ 97,414	$ 185,838	$ (2,735)	$ 6,098