Loans and Leases - Allowance for Credit Losses - Reserves (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable Allowance For Credit Losses [Line Items]
Specific		$ 827	$ 2,008	$ 1,153
General		9,096	7,742	7,890
Ending balance		9,923	9,750	9,043	$ 9,701
Unallocated [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
General		132	30	46
Ending balance		132	30	46	457
Real Estate Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Specific		493	937	728
General		5,142	4,894	4,058
Ending balance		5,635	5,831	4,786	3,548
Agricultural Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Specific		1	2
General		192	254	208
Ending balance		193	256	208	209
Commercial and Industrial and Mortgage Warehouse Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Specific		219	918	188
General		2,466	1,476	2,584
Ending balance	[1]	2,685	2,394	2,772	4,279
Consumer Loans Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Specific		114	151	237
General		1,164	1,088	994
Ending balance		$ 1,278	$ 1,239	$ 1,231	$ 1,208

[1] Includes mortgage warehouse lines