Fair Value (Assets and Liabilities Measured at Fair Value on Non-Recurring Basis) (Details) - Fair Value, Measurements, Nonrecurring - Individually Analyzed Loans - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commercial and Industrial Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	$ 4,662	$ 4,985
Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	7,548	8,893
Agricultural Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	548	551
Consumer Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Home Equity Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	369	369
Residential Mortgage Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	507	75
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial and Industrial Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Agricultural Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Consumer Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Home Equity Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Residential Mortgage Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Commercial and Industrial Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Agricultural Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Consumer Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Home Equity Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Residential Mortgage Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Unobservable  Inputs (Level 3) | Commercial and Industrial Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	4,662	4,985
Significant Unobservable  Inputs (Level 3) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	7,548	8,893
Significant Unobservable  Inputs (Level 3) | Agricultural Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	548	551
Significant Unobservable  Inputs (Level 3) | Consumer Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Unobservable  Inputs (Level 3) | Home Equity Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	369	369
Significant Unobservable  Inputs (Level 3) | Residential Mortgage Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	$ 507	$ 75