Fair Value Measurements, Assets or Liabilities Measured at Fair Value on a Non-recurring Basis (Details) - Nonrecurring [Member] - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	$ 2,064	$ 2,396	$ 1,669
Other Real Estate	873	873	873
Total Assets Measured at Fair Value On a Non-Recurring Basis	2,937	3,269	2,542
Commercial Real Estate [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	82
Residential 1st Mortgage [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	1,572	1,584	1,470
Home Equity Lines and Loans [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	60	61	64
Agricultural [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans		400
Commercial [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	212	213
Consumer [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	138	138	135
Real Estate Construction [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Other Real Estate	873	873	873
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Other Real Estate	0	0	0
Total Assets Measured at Fair Value On a Non-Recurring Basis	0	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial Real Estate [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Residential 1st Mortgage [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Home Equity Lines and Loans [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Agricultural [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans		0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Consumer [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Real Estate Construction [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Other Real Estate	0	0	0
Other Observable Inputs (Level 2) [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Other Real Estate	0	0	0
Total Assets Measured at Fair Value On a Non-Recurring Basis	0	0	0
Other Observable Inputs (Level 2) [Member] | Commercial Real Estate [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0
Other Observable Inputs (Level 2) [Member] | Residential 1st Mortgage [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Other Observable Inputs (Level 2) [Member] | Home Equity Lines and Loans [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Other Observable Inputs (Level 2) [Member] | Agricultural [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans		0
Other Observable Inputs (Level 2) [Member] | Commercial [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0
Other Observable Inputs (Level 2) [Member] | Consumer [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	0	0	0
Other Observable Inputs (Level 2) [Member] | Real Estate Construction [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Other Real Estate	0	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	2,064	2,396	1,669
Other Real Estate	873	873	873
Total Assets Measured at Fair Value On a Non-Recurring Basis	2,937	3,269	2,542
Significant Unobservable Inputs (Level 3) [Member] | Commercial Real Estate [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	82
Significant Unobservable Inputs (Level 3) [Member] | Residential 1st Mortgage [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	1,572	1,584	1,470
Significant Unobservable Inputs (Level 3) [Member] | Home Equity Lines and Loans [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	60	61	64
Significant Unobservable Inputs (Level 3) [Member] | Agricultural [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans		400
Significant Unobservable Inputs (Level 3) [Member] | Commercial [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	212	213
Significant Unobservable Inputs (Level 3) [Member] | Consumer [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Impaired Loans	138	138	135
Significant Unobservable Inputs (Level 3) [Member] | Real Estate Construction [Member]
Fair Value on Non-recurring Basis by Fair Value Hierarchy [Abstract]
Other Real Estate	$ 873	$ 873	$ 873