Loans (Non-accrual and Past Due Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	$ 10,119
Non-Accrual	22,878	$ 13,802
Loans Past Due Over 89 Days Still Accruing	0	190
Commercial and Industrial Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	1,350
Non-Accrual	8,519
Loans Past Due Over 89 Days Still Accruing	0
Commercial Real Estate Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	5,657
Non-Accrual	10,282	3,433
Loans Past Due Over 89 Days Still Accruing	0	0
Agricultural Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	2,015
Non-Accrual	2,643	2,739
Loans Past Due Over 89 Days Still Accruing	0	0
Leases
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	0
Non-Accrual	0
Loans Past Due Over 89 Days Still Accruing	0
Home Equity Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	200
Non-Accrual	200	79
Loans Past Due Over 89 Days Still Accruing	0	0
Consumer Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	61
Non-Accrual	105	115
Loans Past Due Over 89 Days Still Accruing	0	0
Credit Cards
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	66
Non-Accrual	66
Loans Past Due Over 89 Days Still Accruing	0
Residential Mortgage Loans
Financing Receivable, Past Due [Line Items]
Non-Accrual With No Allowance for Credit Loss	770
Non-Accrual	1,063	2,496
Loans Past Due Over 89 Days Still Accruing	$ 0	$ 0