Fair Value Measurements (Financial Assets And Financial Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
US Government-Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	$ 320,820	$ 306,993
US Government-Sponsored Enterprises [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	320,820	306,993
US Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	84,797	79,130
US Government Agencies [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	84,797	79,130
Private Label [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	3,143	3,464
Private Label [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	3,143	3,464
Obligations Of States And Political Subdivisions Thereof [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	124,159	115,382
Obligations Of States And Political Subdivisions Thereof [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	124,159	115,382
Derivative Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	1,353	2,069
Derivative Assets [Member] | Level 2 Inputs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, at fair value on a recurring basis	$ 1,353	$ 2,069