Loans, Net - Loans identified as impaired by class of loan (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Recorded Investment [Abstract]
With no related allowance recorded	$ 8,675	$ 9,162
With an allowance recorded	10,996	11,682
Total	19,671	20,844
Unpaid Principal Balance [Abstract]
With no related allowance recorded	8,746	9,232
With an allowance recorded	14,047	14,734
Total	22,793	23,966
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	2,260	2,664
Total	2,260	2,664
Average Recorded Investment [Abstract]
With no related allowance recorded	8,762	9,202
With an allowance recorded	11,871	13,644
Total	20,633	22,846
Interest Income Recognized [Abstract]
With no related allowance recorded	63	254
With an allowance recorded	47	284
Total	110	538
Construction [Member]
Recorded Investment [Abstract]
With no related allowance recorded	79	100
With an allowance recorded	0	103
Unpaid Principal Balance [Abstract]
With no related allowance recorded	79	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	126	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	7,903	7,903
With an allowance recorded	0	0
Unpaid Principal Balance [Abstract]
With no related allowance recorded	7,903	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	7,903	7,903
With an allowance recorded	0	0
Interest Income Recognized [Abstract]
With no related allowance recorded	59	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	3,860	4,426
Unpaid Principal Balance [Abstract]
With no related allowance recorded	277	736
With an allowance recorded	3,912	4,478
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,086	1,120
Average Recorded Investment [Abstract]
With no related allowance recorded	242	703
With an allowance recorded	4,004	4,547
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	7	27
Other real estate loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	4,179	4,196
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	4,179	4,196
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	330	464
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	4,285	4,224
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	39	157
Commercial loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	451	458
With an allowance recorded	1,074	1,059
Unpaid Principal Balance [Abstract]
With no related allowance recorded	487	493
With an allowance recorded	4,073	4,059
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	57	27
Average Recorded Investment [Abstract]
With no related allowance recorded	491	490
With an allowance recorded	1,140	2,315
Interest Income Recognized [Abstract]
With no related allowance recorded	4	17
With an allowance recorded	1	100
Consumer loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,883	1,898
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,883	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	2,442	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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