Loans and Allowance for Losses - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan Losses
Beginning balance				$ 7,017					$ 7,017
Provision for losses	$ 2,430	$ 760	$ 578	(264)	$ 146	$ 99	$ 424	$ (431)	3,504	$ 238	$ 1,708
Charge-offs									(67)	(17)	(327)
Ending balance	10,454				7,017				10,454	7,017
Reserve for Losses
Beginning balance				2,167					2,167
(Release of)/provision for reserve for losses									(3)	97	50
Charge-offs									(67)	(17)	(327)
Ending balance	2,164				2,167				2,164	2,167
Total Allowance for Losses
Beginning balance				9,184				8,866	9,184	8,866	7,435
Provision for/(release of) losses									3,501	335	1,758
Charge-offs									(67)	(17)	(327)
Ending balance	12,618				9,184				12,618	9,184	8,866
Crops
Allowance for Loan Losses
Charge-offs									0	0	(228)
Reserve for Losses
Charge-offs									0	0	(228)
Total Allowance for Losses
Beginning balance				4,394				4,081	4,394	4,081	3,365
Provision for/(release of) losses									810	313	944
Charge-offs									0	0	(228)
Ending balance	5,204				4,394				5,204	4,394	4,081
Permanent Plantings
Allowance for Loan Losses
Charge-offs									0	0	(70)
Reserve for Losses
Charge-offs									0	0	(70)
Total Allowance for Losses
Beginning balance				2,126				2,469	2,126	2,469	1,723
Provision for/(release of) losses									383	(343)	816
Charge-offs									0	0	(70)
Ending balance	2,509				2,126				2,509	2,126	2,469
Livestock
Allowance for Loan Losses
Charge-offs									0	0	(13)
Reserve for Losses
Charge-offs									0	0	(13)
Total Allowance for Losses
Beginning balance				1,460				1,211	1,460	1,211	1,375
Provision for/(release of) losses									2,198	249	(151)
Charge-offs									0	0	(13)
Ending balance	3,658				1,460				3,658	1,460	1,211
Part-time Farm
Allowance for Loan Losses
Charge-offs									(67)	(17)	(16)
Reserve for Losses
Charge-offs									(67)	(17)	(16)
Total Allowance for Losses
Beginning balance				474				481	474	481	405
Provision for/(release of) losses									21	10	92
Charge-offs									(67)	(17)	(16)
Ending balance	428				474				428	474	481
Ag. Storage and Processing
Allowance for Loan Losses
Charge-offs									0	0	0
Reserve for Losses
Charge-offs									0	0	0
Total Allowance for Losses
Beginning balance				720				606	720	606	533
Provision for/(release of) losses									94	114	73
Charge-offs									0	0	0
Ending balance	814				720				814	720	606
Other
Allowance for Loan Losses
Charge-offs									0	0	0
Reserve for Losses
Charge-offs									0	0	0
Total Allowance for Losses
Beginning balance				10				18	10	18	34
Provision for/(release of) losses									(5)	(8)	(16)
Charge-offs									0	0	0
Ending balance	5				10				5	10	18
Allowance for Loan Losses
Allowance for Loan Losses
Beginning balance				7,017				6,796	7,017	6,796	5,415
Provision for losses									3,504	238	1,708
Charge-offs									(67)	(17)	(327)
Ending balance	10,454				7,017				10,454	7,017	6,796
Reserve for Losses
Charge-offs									(67)	(17)	(327)
Total Allowance for Losses
Charge-offs									(67)	(17)	(327)
Reserve for Losses
Allowance for Loan Losses
Charge-offs									0	0	0
Reserve for Losses
Beginning balance				$ 2,167				$ 2,070	2,167	2,070	2,020
(Release of)/provision for reserve for losses									(3)	97	50
Charge-offs									0	0	0
Ending balance	$ 2,164				$ 2,167				2,164	2,167	2,070
Total Allowance for Losses
Charge-offs									$ 0	$ 0	$ 0