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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, 2019 | Dec. 31, 2018
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | $ 1,845 | $ 3,122
Equity securities | 30,685 | 34,697
Fixed income securities | 49,571 | 34,472
Total Plan investments | 87,827 | 75,188
Foreign Currencies [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 16 | 28
Short Term Investment Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 1,829 | 3,094
Common Stock [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 11,931
Depository Receipts [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 203
Commingled Pension Trust Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 30,685 | 22,468
Fixed income securities | 49,566 | 20,051
Total Plan investments | 5,726 | 2,897
Preferred Equity [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 95
Collateralized Mortgage Obligations [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 750
All Other Corporate Bonds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | 5 | 2,928
Government National Mortgage Association [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 144
Government Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 10,599
Level 1 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 16 | 28
Equity securities |  | 12,229
Total Plan investments | 16 | 12,257
Level 1 Inputs [Member] | Foreign Currencies [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 16 | 28
Level 1 Inputs [Member] | Common Stock [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 11,931
Level 1 Inputs [Member] | Depository Receipts [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 203
Level 1 Inputs [Member] | Preferred Equity [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities |  | 95
Level 2 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 1,829 | 3,094
Equity securities | 30,685 | 22,468
Fixed income securities | 49,571 | 34,472
Total Plan investments | 87,811 | 60,034
Level 2 Inputs [Member] | Short Term Investment Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Cash equivalents | 1,829 | 3,094
Level 2 Inputs [Member] | Commingled Pension Trust Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity securities | 30,685 | 22,468
Fixed income securities | 49,566 | 20,051
Total Plan investments | 5,726 |
Level 2 Inputs [Member] | Collateralized Mortgage Obligations [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 750
Level 2 Inputs [Member] | All Other Corporate Bonds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities | $ 5 | 2,928
Level 2 Inputs [Member] | Government National Mortgage Association [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 144
Level 2 Inputs [Member] | Government Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fixed income securities |  | 10,599
Level 3 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total Plan investments |  | 2,897
Level 3 Inputs [Member] | Commingled Pension Trust Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total Plan investments |  | $ 2,897

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