Quarterly Financial Comparison (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended																				12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015		Sep. 30, 2015		Jun. 30, 2015		Mar. 31, 2015		Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest and dividend income	$ 12,584	$ 12,223	$ 11,928	$ 11,312	$ 11,208		$ 11,002		$ 10,935		$ 10,728		$ 10,663		$ 10,667		$ 10,254		$ 10,175		$ 48,047	$ 43,873	$ 41,759
Interest expense	2,111	2,079	2,033	1,919	1,860		1,918		1,902		1,665		1,610		1,663		1,684		1,741		8,142	7,345	6,698
Net interest income	10,473	10,144	9,895	9,393	9,348		9,084		9,033		9,063		9,053		9,004		8,570		8,434		39,905	36,528	35,061
Provision for loan losses	670	698	564	427	362		501		392		178		1,502		385		563		203		2,359	1,433	2,653
Net interest income after provision for loan losses	9,803	9,446	9,331	8,966	8,986		8,583		8,641		8,885		7,551		8,619		8,007		8,231		37,546	35,095	32,408
Noninterest income	891	842	777	850	909		466		962		962		1,225		1,118		855		895		3,360	3,299	4,093
Noninterest expense	7,316	7,311	7,292	7,240	7,556		7,031		6,888		6,943		6,652		6,485		6,767		6,331		29,159	28,418	26,235
Income before income taxes	3,378	2,977	2,816	2,576	2,339		2,018		2,715		2,904		2,124		3,252		2,095		2,795		11,747	9,976	10,266
Provision for income taxes	1,356	1,014	1,078	968	811		735		1,004		1,083		579		1,363		760		1,074		4,416	3,633	3,776
Net income					1,528		1,283		1,711		1,821		1,545		1,889		1,335		1,721		7,331	6,343	6,490
Preferred stock dividends											23		50		50		50		50			23	200
Net income available to common shareholders	$ 2,022	$ 1,963	$ 1,738	$ 1,608	$ 1,528		$ 1,283		$ 1,711		$ 1,798		$ 1,495		$ 1,839		$ 1,285		$ 1,671		$ 7,331	$ 6,320	$ 6,290
Earnings Per Common Share
Basic	$ 0.44	$ 0.43	$ 0.38	$ 0.35	$ 0.33	[1]	$ 0.28	[1]	$ 0.37	[1]	$ 0.38	[1]	$ 0.32	[1]	$ 0.40	[1]	$ 0.28	[1]	$ 0.36	[1]	$ 1.59	$ 1.36	$ 1.35
Diluted	$ 0.44	$ 0.42	$ 0.38	$ 0.35	$ 0.33	[1]	$ 0.27	[1]	$ 0.37	[1]	$ 0.38	[1]	$ 0.32	[1]	$ 0.39	[1]	$ 0.28	[1]	$ 0.36	[1]	$ 1.59	$ 1.35	$ 1.35
Parent Company [Member]
Interest expense																					$ 1,795	$ 1,599	$ 312
Net interest income																					3,724	1,227	3,194
Income before income taxes																					1,614	(194)	1,767
Provision for income taxes																					(1,321)	(1,009)	(589)
Net income																					7,331	6,343	6,490
Preferred stock dividends																						23	200
Net income available to common shareholders																					$ 7,331	$ 6,320	$ 6,290

[1] Earnings per share are based upon quarterly results and, when added, may not total the annual earnings per share amounts.