Employee Benefit Plans (The Major Categories Of Plan Assets Measured At Fair Value On a Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	$ 5,361	$ 4,553
Equity securities	41,824	36,019
Fixed income securities	33,522	32,043
Total Plan investments	83,348	75,252
Foreign Currencies [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	726	99
Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	10,117	9,783
Short Term Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	4,635	4,454
Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	14,523	13,326
Depository Receipts [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	368	391
Commingled Pension Trust Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	26,613	22,302
Fixed income securities	19,524	18,151
Other investments	2,641	2,637
Preferred Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	320
Collateralized Mortgage Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	585	633
All Other Corporate Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	3,068	2,862
Federal National Mortgage Association [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	167	579
Mortgage-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	61	35
Level 1 Inputs [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	726	99
Equity securities	15,211	13,717
Total Plan investments	15,937	13,816
Level 1 Inputs [Member] | Foreign Currencies [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	726	99
Level 1 Inputs [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	14,523	13,326
Level 1 Inputs [Member] | Depository Receipts [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	368	391
Level 1 Inputs [Member] | Preferred Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	320
Level 2 Inputs [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	4,635	4,454
Equity securities	26,613	22,302
Fixed income securities	33,522	32,043
Total Plan investments	64,770	58,799
Level 2 Inputs [Member] | Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	10,117	9,783
Level 2 Inputs [Member] | Short Term Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents	4,635	4,454
Level 2 Inputs [Member] | Commingled Pension Trust Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities	26,613	22,302
Fixed income securities	19,524	18,151
Level 2 Inputs [Member] | Collateralized Mortgage Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	585	633
Level 2 Inputs [Member] | All Other Corporate Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	3,068	2,862
Level 2 Inputs [Member] | Federal National Mortgage Association [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	167	579
Level 2 Inputs [Member] | Mortgage-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities	61	35
Level 3 Inputs [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents
Equity securities
Fixed income securities
Total Plan investments	2,641	2,637
Level 3 Inputs [Member] | Foreign Currencies [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents
Level 3 Inputs [Member] | Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities
Level 3 Inputs [Member] | Short Term Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash equivalents
Level 3 Inputs [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities
Level 3 Inputs [Member] | Depository Receipts [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities
Level 3 Inputs [Member] | Commingled Pension Trust Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities
Fixed income securities
Other investments	2,641	2,637
Level 3 Inputs [Member] | Preferred Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Equity securities
Level 3 Inputs [Member] | Collateralized Mortgage Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities
Level 3 Inputs [Member] | All Other Corporate Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities
Level 3 Inputs [Member] | Federal National Mortgage Association [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities
Level 3 Inputs [Member] | Mortgage-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income securities