Loans and Allowance (Non-Accrual Loan, Segregated by Class of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 5,828	$ 5,220
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	1,377	1,107
First Mortgage [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	3,616	3,409
Second Mortgage [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	223	309
Automobile Loan [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	11	22
Boat/RVs [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	367	198
Other [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	52	16
Commercial and Industrial [Member] | Commercial Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual loans	$ 182	$ 159