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Employee Benefit Plans (Plan's Target Asset Allocation And Actual Asset Allocation) (Details) | Dec. 31, 2020 | Dec. 31, 2019
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Defined Benefit Plan Disclosure [Line Items] |  |
Actual Allocation | 99.00% | 98.00%
Cash and Cash Equivalents [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 0.00% | 0.00%
Actual Allocation | 0.00% | 0.00%
Equity Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 28.25% | 28.25%
Actual Allocation | 31.56% | 31.75%
Fixed Income Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 59.75% | 59.75%
Actual Allocation | 62.60% | 57.65%
Alternative Investments [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation | 12.00% | 12.00%
Actual Allocation | 5.84% | 10.60%

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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