Loans, Net - Loans identified as impaired by class of loan (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Recorded Investment [Abstract]
With no related allowance recorded	$ 10,221	$ 9,162
With an allowance recorded	9,161	11,682
Total	19,382	20,844
Unpaid Principal Balance [Abstract]
With no related allowance recorded	13,256	9,232
With an allowance recorded	9,214	14,734
Total	22,470	23,966
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	2,133	2,664
Total	2,133	2,664
Average Recorded Investment [Abstract]
With no related allowance recorded	10,503	9,202
With an allowance recorded	9,220	13,644
Total	19,723	22,846
Interest Income Recognized [Abstract]
With no related allowance recorded	126	254
With an allowance recorded	99	284
Total	225	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	7,917	7,903
With an allowance recorded	0	0
Unpaid Principal Balance [Abstract]
With no related allowance recorded	7,917	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	7,910	7,903
With an allowance recorded	0	0
Interest Income Recognized [Abstract]
With no related allowance recorded	118	237
With an allowance recorded	0	0
Secured by 1-4 family residential [Member]
Recorded Investment [Abstract]
With no related allowance recorded	242	701
With an allowance recorded	4,254	4,426
Unpaid Principal Balance [Abstract]
With no related allowance recorded	277	736
With an allowance recorded	4,307	4,478
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,094	1,120
Average Recorded Investment [Abstract]
With no related allowance recorded	243	703
With an allowance recorded	4,273	4,547
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	21	27
Other real estate loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	1,126	0
With an allowance recorded	2,991	4,196
Unpaid Principal Balance [Abstract]
With no related allowance recorded	1,126	0
With an allowance recorded	2,991	4,196
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	222	464
Average Recorded Investment [Abstract]
With no related allowance recorded	1,133	0
With an allowance recorded	3,001	4,224
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	77	157
Commercial loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	906	458
With an allowance recorded	46	1,059
Unpaid Principal Balance [Abstract]
With no related allowance recorded	3,906	493
With an allowance recorded	46	4,059
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	27
Average Recorded Investment [Abstract]
With no related allowance recorded	1,186	490
With an allowance recorded	62	2,315
Interest Income Recognized [Abstract]
With no related allowance recorded	8	17
With an allowance recorded	1	100
Consumer loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,870	1,898
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,870	1,898
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	787	1,000
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,884	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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