Loans - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 8,974	$ 7,995	$ 8,591	$ 7,981	$ 7,981
Charge-offs	(123)	(1,036)	(638)	(1,108)
Recoveries	74	1,686	672	1,772
Provision	0	0	300	0
Ending Balance	8,925	8,645	8,925	8,645	8,591
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	752	1,139	648	1,117	1,117
Charge-offs	(18)	(357)	(18)	(357)
Recoveries	25	64	69	90
Provision	426	190	486	186
Ending Balance	1,185	1,036	1,185	1,036	648
Agriculture & AG RE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	119	50	97	69	69
Charge-offs	0	0	0	0
Recoveries	1	0	55	0
Provision	(17)	15	(49)	(4)
Ending Balance	103	65	103	65	97
Construction, Land & Development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	516	437	523	711	711
Charge-offs	0	0	0	(3)
Recoveries	5	6	24	27
Provision	(69)	(47)	(95)	(339)
Ending Balance	452	396	452	396	523
Commercial RE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	5,541	4,018	5,681	3,999	3,999
Charge-offs	(17)	(614)	(520)	(615)
Recoveries	26	1,585	471	1,607
Provision	(307)	196	(389)	194
Ending Balance	5,243	5,185	5,243	5,185	5,681
1-4 Family Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	2,042	2,342	1,628	2,075	2,075
Charge-offs	(88)	(63)	(97)	(130)
Recoveries	15	12	51	21
Provision	(36)	(340)	351	(15)
Ending Balance	1,933	1,951	1,933	1,951	1,628
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	4	9	14	10	10
Charge-offs	0	(2)	(3)	(3)
Recoveries	2	19	2	27
Provision	3	(14)	(4)	(22)
Ending Balance	$ 9	$ 12	$ 9	$ 12	$ 14