Fair Value (Assets and Liabilities Measured at Fair Value on Non-Recurring Basis) (Details) - Fair Value, Measurements, Nonrecurring - Impaired Loans - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Commercial and Industrial Loans and Leases
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	$ 2,853	$ 3,354
Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	3,240	3,438
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial and Industrial Loans and Leases
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Commercial and Industrial Loans and Leases
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Other Observable Inputs (Level 2) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	0	0
Significant Unobservable Inputs (Level 3) | Commercial and Industrial Loans and Leases
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	2,853	3,354
Significant Unobservable Inputs (Level 3) | Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets	$ 3,240	$ 3,438