Fair Value Measurements, Quantitative Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)
Impaired Loans [Member] | Residential 1st Mortgages [Member] | Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Impaired Loans	$ 480
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Impaired Loans [Member] | Residential 1st Mortgages [Member] | Sales Comparison Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	2.00%
Impaired Loans [Member] | Residential 1st Mortgages [Member] | Sales Comparison Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	4.00%
Impaired Loans [Member] | Residential 1st Mortgages [Member] | Sales Comparison Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	3.00%
Impaired Loans [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Impaired Loans	$ 83
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Impaired Loans [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	1.00%
Impaired Loans [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	2.00%
Impaired Loans [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	2.00%
Impaired Loans [Member] | Agricultural [Member] | Income Approach [Member]
Quantitative Information [Abstract]
Impaired Loans	$ 286
Unobservable inputs	Capitalization Rate
Impaired Loans [Member] | Agricultural [Member] | Income Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Impaired Loans [Member] | Agricultural [Member] | Income Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Impaired Loans [Member] | Agricultural [Member] | Income Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Impaired Loans [Member] | Agricultural [Member] | Collateral Approach [Member]
Quantitative Information [Abstract]
Impaired Loans	$ 211
Unobservable inputs	Collateral Value
Impaired Loans [Member] | Agricultural [Member] | Collateral Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Capitalization rate	10.00%
Impaired Loans [Member] | Agricultural [Member] | Collateral Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Capitalization rate	10.00%
Impaired Loans [Member] | Agricultural [Member] | Collateral Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Capitalization rate	10.00%
Impaired Loans [Member] | Commercial [Member] | Income Approach [Member]
Quantitative Information [Abstract]
Impaired Loans	$ 833
Unobservable inputs	Capitalization Rate
Impaired Loans [Member] | Commercial [Member] | Income Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Impaired Loans [Member] | Commercial [Member] | Income Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Impaired Loans [Member] | Commercial [Member] | Income Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Capitalization rate	16.00%
Other Real Estate [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Other Real Estate	$ 785
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Other Real Estate [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] | Home Equity Lines and Loans [Member] | Sales Comparison Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] | Real Estate Construction [Member] | Sales Comparison Approach [Member]
Quantitative Information [Abstract]
Other Real Estate	$ 2,960
Unobservable inputs	Adjustment for Difference Between Comparable Sales
Other Real Estate [Member] | Real Estate Construction [Member] | Sales Comparison Approach [Member] | Minimum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] | Real Estate Construction [Member] | Sales Comparison Approach [Member] | Maximum [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%
Other Real Estate [Member] | Real Estate Construction [Member] | Sales Comparison Approach [Member] | Weighted Average [Member]
Quantitative Information [Abstract]
Adjustment for difference between comparable sales	10.00%