Loans, Net - Loans identified as impaired by class of loan (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Recorded Investment [Abstract]
With no related allowance recorded	$ 10,002	$ 9,162
With an allowance recorded	10,431	11,682
Total	20,433	20,844
Unpaid Principal Balance [Abstract]
With no related allowance recorded	10,037	9,232
With an allowance recorded	13,483	14,734
Total	23,520	23,966
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	2,612	2,664
Total	2,612	2,664
Average Recorded Investment [Abstract]
With no related allowance recorded	10,021	9,202
With an allowance recorded	10,806	13,644
Total	20,827	22,846
Interest Income Recognized [Abstract]
With no related allowance recorded	234	254
With an allowance recorded	185	284
Total	419	538
Construction [Member]
Recorded Investment [Abstract]
With no related allowance recorded	30	100
With an allowance recorded	0	103
Unpaid Principal Balance [Abstract]
With no related allowance recorded	30	100
With an allowance recorded	0	103
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	53
Average Recorded Investment [Abstract]
With no related allowance recorded	31	106
With an allowance recorded	0	109
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Secured by farmland [Member]
Recorded Investment [Abstract]
With no related allowance recorded	7,931	7,903
With an allowance recorded	0	0
Unpaid Principal Balance [Abstract]
With no related allowance recorded	7,931	7,903
With an allowance recorded	0	0
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Average Recorded Investment [Abstract]
With no related allowance recorded	7,917	7,903
With an allowance recorded	0	0
Interest Income Recognized [Abstract]
With no related allowance recorded	217	237
With an allowance recorded	0	0
Secured by 1-4 family residential [Member]
Recorded Investment [Abstract]
With no related allowance recorded	73	701
With an allowance recorded	4,289	4,426
Unpaid Principal Balance [Abstract]
With no related allowance recorded	108	736
With an allowance recorded	4,341	4,478
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,214	1,120
Average Recorded Investment [Abstract]
With no related allowance recorded	73	703
With an allowance recorded	4,323	4,547
Interest Income Recognized [Abstract]
With no related allowance recorded	2	0
With an allowance recorded	46	27
Other real estate loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	1,089	0
With an allowance recorded	3,865	4,196
Unpaid Principal Balance [Abstract]
With no related allowance recorded	1,089	0
With an allowance recorded	3,865	4,196
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	406	464
Average Recorded Investment [Abstract]
With no related allowance recorded	1,115	0
With an allowance recorded	3,890	4,224
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	139	157
Commercial loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	879	458
With an allowance recorded	406	1,059
Unpaid Principal Balance [Abstract]
With no related allowance recorded	879	493
With an allowance recorded	3,406	4,059
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	190	27
Average Recorded Investment [Abstract]
With no related allowance recorded	885	490
With an allowance recorded	708	2,315
Interest Income Recognized [Abstract]
With no related allowance recorded	15	17
With an allowance recorded	0	100
Consumer loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,871	1,898
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,871	1,898
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	802	1,000
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,885	2,449
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	$ 0	$ 0

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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