Loans, Net - Loans identified as impaired by class of loan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Recorded Investment [Abstract]
With no related allowance recorded	$ 10,633	$ 9,162
With an allowance recorded	10,136	11,682
Total	20,769	20,844
Unpaid Principal Balance [Abstract]
With no related allowance recorded	13,669	9,232
With an allowance recorded	10,187	14,734
Total	23,856	23,966
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	3,838	2,664
Total	3,838	2,664
Average Recorded Investment [Abstract]
With no related allowance recorded	10,733	9,202
With an allowance recorded	11,173	13,644
Total	21,906	22,846
Interest Income Recognized [Abstract]
With no related allowance recorded	257	254
With an allowance recorded	200	284
Total	457	538
Real Estate Loans Construction [Member]
Recorded Investment [Abstract]
With no related allowance recorded	28	100
With an allowance recorded	0	103
Unpaid Principal Balance [Abstract]
With no related allowance recorded	28	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	28	106
With an allowance recorded	0	109
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Real Estate Loans Secured by Farmland [Member]
Recorded Investment [Abstract]
With no related allowance recorded	7,972	7,903
With an allowance recorded	0	0
Unpaid Principal Balance [Abstract]
With no related allowance recorded	7,972	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	7,951	7,903
With an allowance recorded	0	0
Interest Income Recognized [Abstract]
With no related allowance recorded	239	237
With an allowance recorded	0	0
Real Estate Loans Secured by 1 - 4 Family Residential [Member]
Recorded Investment [Abstract]
With no related allowance recorded	72	701
With an allowance recorded	1,275	4,426
Unpaid Principal Balance [Abstract]
With no related allowance recorded	108	736
With an allowance recorded	1,326	4,478
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	251	1,120
Average Recorded Investment [Abstract]
With no related allowance recorded	72	703
With an allowance recorded	1,239	4,547
Interest Income Recognized [Abstract]
With no related allowance recorded	2	0
With an allowance recorded	49	27
Other Real Estate Loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	1,976	0
With an allowance recorded	2,971	4,196
Unpaid Principal Balance [Abstract]
With no related allowance recorded	1,976	0
With an allowance recorded	2,971	4,196
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	206	464
Average Recorded Investment [Abstract]
With no related allowance recorded	1,976	0
With an allowance recorded	2,975	4,224
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	151	157
Commercial Loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	585	458
With an allowance recorded	4,019	1,059
Unpaid Principal Balance [Abstract]
With no related allowance recorded	3,585	493
With an allowance recorded	4,019	4,059
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	2,539	27
Average Recorded Investment [Abstract]
With no related allowance recorded	706	490
With an allowance recorded	5,088	2,315
Interest Income Recognized [Abstract]
With no related allowance recorded	16	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	842	1,000
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	1,871	2,449
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	$ 0	$ 0

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