Loans and Allowance (Newly Restructured Loans by Type) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Combination	$ 140
Total modification	140
Commercial Segment [Member] | Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term	61	$ 72
Total modification	61	72
Consumer [Member] | First Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Combination	59	67
Total modification	59	$ 67
Consumer [Member] | Second Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term	36
Total modification	$ 36