Fair Values of Financial Instruments (Fair Value Measurement of Assets Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	$ 354,145	$ 277,378
Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	867	525
Derivative liability	867	525
Mortgage-backed securities, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	94,263	67,798
Collateralized mortgage obligations, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	109,617	87,250
Municipals
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	138,478	110,495
Corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	11,787	11,835
Fair Value, Inputs, Level 1 | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset
Derivative liability
Fair Value, Inputs, Level 1 | Mortgage-backed securities, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale
Fair Value, Inputs, Level 1 | Collateralized mortgage obligations, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale
Fair Value, Inputs, Level 1 | Municipals
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale
Fair Value, Inputs, Level 1 | Corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale
Fair Value, Inputs, Level 2 | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	867	525
Derivative liability	867	525
Fair Value, Inputs, Level 2 | Mortgage-backed securities, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	94,263	67,798
Fair Value, Inputs, Level 2 | Collateralized mortgage obligations, Government sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	109,617	87,250
Fair Value, Inputs, Level 2 | Municipals
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	138,478	110,495
Fair Value, Inputs, Level 2 | Corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	9,066	9,114
Fair Value, Inputs, Level 3 | Corporate obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, available for sale	$ 2,721	$ 2,721