Loans, Net - Summary of loan classifications by class of loan (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	$ 824,551	$ 805,681	$ 761,915
Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	780,526	756,048
Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	17,116	20,854
Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	24,562	25,920
Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	2,347	2,858
Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	1
Construction [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	43,254	39,673	36,702
Construction [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	37,533	30,114
Construction [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	5,642	9,024
Construction [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	79	535
Construction [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Construction [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Secured by farmland [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	18,945	19,062
Secured by farmland [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	11,042	10,566
Secured by farmland [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Secured by farmland [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	7,903	8,496
Secured by farmland [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Secured by farmland [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Secured by 1-4 family residential [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	288,855	280,096	267,287
Secured by 1-4 family residential [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	281,582	271,721
Secured by 1-4 family residential [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	878	896
Secured by 1-4 family residential [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	6,268	6,818
Secured by 1-4 family residential [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	127	661
Secured by 1-4 family residential [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Other real estate loans [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	264,456	258,035	253,246
Other real estate loans [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	250,266	243,768
Other real estate loans [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	6,988	7,254
Other real estate loans [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	6,023	5,827
Other real estate loans [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	1,179	1,186
Other real estate loans [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Commercial [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	189,945	190,482	165,757
Commercial [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	182,969	183,532
Commercial [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	3,573	3,638
Commercial [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	2,362	2,301
Commercial [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	1,041	1,011
Commercial [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Consumer loans [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	19,096	18,333	$ 19,308
Consumer loans [Member] | Pass [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	17,134	16,347
Consumer loans [Member] | Special Mention [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	35	42
Consumer loans [Member] | Substandard [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	1,927	1,943
Consumer loans [Member] | Doubtful [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	0	0
Consumer loans [Member] | Loss [Member]
Summary of loan classifications by class of loan [Abstract]
Summary of loan quality by class of loan	$ 0	$ 1