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Employee Benefit Plans (Changes In Fair Value Of Plan Assets) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of period | $ 75,188 | $ 83,348
Fair value of plan assets at end of period | 87,827 | 75,188
Level 3 Inputs [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of period | 2,897 | 2,641
Realized gain | 881 |
Sales | (2,873) |
Unrealized gain | $ (905) | 256
Fair value of plan assets at end of period |  | $ 2,897

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