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Employee Benefit Plans (The Major Categories Of Plan Assets Measured At Fair Value On a Recurring Basis) (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | $ 4,553 | $ 3,780
Equity securities | 36,019 | 34,166
Fixed income securities | 32,043 | 31,742
Total Plan investments | 75,252 | 72,358
Foreign Currencies [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 99 | 35
Government Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 9,783 | 7,180
Short Term Investment Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 4,454 | 3,745
Common Stock [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 13,326 | 13,083
Depository Receipts [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 391 | 336
Commingled Pension Trust Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 22,302 | 10,557
Fixed income securities | 18,151 | 17,889
Other investments | 2,637 | 2,670
Exchange Traded Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 10,190
Collateralized Mortgage Obligations [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 633 | 608
All Other Corporate Bonds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 2,862 | 3,439
Federal Home Loan Mortgage Corporation [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 276
Federal National Mortgage Association [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 579 | 1,966
Government National Mortgage Association Certificates And Obligations Gnma Two [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 384
Mortgage-Backed Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 35 |
Level 1 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 99 | 35
Equity securities | 13,717 | 23,609
Total Plan investments | 13,816 | 23,644
Level 1 Inputs [Member] | Foreign Currencies [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 99 | 35
Level 1 Inputs [Member] | Common Stock [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 13,326 | 13,083
Level 1 Inputs [Member] | Depository Receipts [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 391 | 336
Level 1 Inputs [Member] | Exchange Traded Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 10,190
Level 2 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 4,454 | 3,745
Equity securities | 22,302 | 10,557
Fixed income securities | 32,043 | 31,742
Total Plan investments | 58,799 | 46,044
Level 2 Inputs [Member] | Government Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 9,783 | 7,180
Level 2 Inputs [Member] | Short Term Investment Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 4,454 | 3,745
Level 2 Inputs [Member] | Commingled Pension Trust Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 22,302 | 10,557
Fixed income securities | 18,151 | 17,889
Level 2 Inputs [Member] | Collateralized Mortgage Obligations [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 633 | 608
Level 2 Inputs [Member] | All Other Corporate Bonds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 2,862 | 3,439
Level 2 Inputs [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 276
Level 2 Inputs [Member] | Federal National Mortgage Association [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 579 | 1,966
Level 2 Inputs [Member] | Government National Mortgage Association Certificates And Obligations Gnma Two [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 384
Level 2 Inputs [Member] | Mortgage-Backed Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 35 |
Level 3 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents |  |
Equity securities |  |
Fixed income securities |  |
Total Plan investments | 2,637 | 2,670
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 | 2,637 | 2,670
Level 3 Inputs [Member] | Exchange Traded Funds [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 Home Loan Mortgage Corporation [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] | Government National Mortgage Association Certificates And Obligations Gnma Two [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 |  |

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