Unaudited Condensed Consolidated Statements of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2015	7,500
Beginning balance at Dec. 31, 2015	$ 937	$ 51,608	$ 120,371	$ 2,782	$ 175,698
Net income			14,060		14,060
Other comprehensive income				339	339
Cash dividends declared – common			(1,575)		(1,575)
Shares issued under director compensation plan (in shares)	2
Shares issued under director compensation plan		62			62
Shares issued pursuant to employee stock purchase plan (in shares)	5
Shares issued pursuant to employee stock purchase plan	$ 1	115			116
Expense related to employee stock purchase plan		24			24
Balance (in shares) at Sep. 30, 2016	7,507
Ending balance at Sep. 30, 2016	$ 938	51,809	132,856	3,121	188,724
Beginning balance at Jun. 30, 2016				7,097
Net income					4,324
Other comprehensive income				(3,976)	(3,976)
Balance (in shares) at Sep. 30, 2016	7,507
Ending balance at Sep. 30, 2016	$ 938	51,809	132,856	3,121	188,724
Balance (in shares) at Dec. 31, 2016	7,509
Beginning balance at Dec. 31, 2016	$ 939	51,885	134,650	(3,408)	184,066
Net income			13,123		13,123
Other comprehensive income				2,478	2,478
Cash dividends declared – common			(2,254)		(2,254)
Shares issued under director compensation plan (in shares)	2
Shares issued under director compensation plan		76			76
Shares issued pursuant to employee stock purchase plan (in shares)	4
Shares issued pursuant to employee stock purchase plan		136			136
Expense related to employee stock purchase plan		23			23
Balance (in shares) at Sep. 30, 2017	7,515
Ending balance at Sep. 30, 2017	$ 939	52,120	145,519	(930)	197,648
Beginning balance at Jun. 30, 2017				(1,056)
Net income					5,312
Other comprehensive income				126	126
Balance (in shares) at Sep. 30, 2017	7,515
Ending balance at Sep. 30, 2017	$ 939	$ 52,120	$ 145,519	$ (930)	$ 197,648