Loans and Allowance (Troubled Debts Restructured) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan		1	4
Pre-Modification Outstanding Recorded Balance		$ 406	$ 2,399
Post-Modification Outstanding Recorded Balance		$ 406	$ 2,406
Commercial Segment [Member] | Construction Loans [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan		1	1
Pre-Modification Outstanding Recorded Balance		$ 83	$ 155
Post-Modification Outstanding Recorded Balance		$ 83	$ 155
Commercial Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan	1		1
Pre-Modification Outstanding Recorded Balance	$ 72		$ 88
Post-Modification Outstanding Recorded Balance	$ 72		$ 83
Consumer [Member] | First Mortgage [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan	7	14	8
Pre-Modification Outstanding Recorded Balance	$ 320	$ 881	$ 287
Post-Modification Outstanding Recorded Balance	$ 324	$ 911	$ 287
Consumer [Member] | Second Mortgage [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan	2	1	3
Pre-Modification Outstanding Recorded Balance	$ 16	$ 39	$ 51
Post-Modification Outstanding Recorded Balance	$ 16	$ 39	$ 51
Consumer [Member] | Automobile Loan [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan		1	2
Pre-Modification Outstanding Recorded Balance		$ 4	$ 25
Post-Modification Outstanding Recorded Balance		$ 4	25
Consumer [Member] | Boat/RVs [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan		3
Pre-Modification Outstanding Recorded Balance		$ 56
Post-Modification Outstanding Recorded Balance		$ 56
Consumer [Member] | Other [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans | loan		2
Pre-Modification Outstanding Recorded Balance		$ 7
Post-Modification Outstanding Recorded Balance		$ 7
Consumer [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Balance			$ 83