Fair Value (Quantitative Information of Fair Value Measurements) (Details) - Impaired Loans - Significant Unobservable Inputs (Level 3) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Commercial and Industrial Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 2,853	$ 3,354
Commercial and Industrial Loans | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	0.00%	0.00%
Commercial and Industrial Loans | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	95.00%	95.00%
Commercial and Industrial Loans | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	88.00%	84.00%
Commercial Real Estate Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 3,240	$ 3,438
Commercial Real Estate Loans | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	17.00%	30.00%
Commercial Real Estate Loans | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	76.00%	76.00%
Commercial Real Estate Loans | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range (Weighted Average)	47.00%	47.00%