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Retirement Benefits (Schedule Of Asset Allocations) (Details) | Dec. 31, 2020
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DB Pension Plans |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 100.00%
DB Pension Plans | Equity securities |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 55.00%
DB Pension Plans | Fixed-income securities |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 34.00%
DB Pension Plans | Multi-asset investments |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 11.00%
OPEB Plan |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 100.00%
OPEB Plan | Equity securities |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 50.00%
OPEB Plan | Fixed-income securities |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 30.00%
OPEB Plan | Multi-asset investments |
Defined Benefit Plan Disclosure [Line Items] |
Asset allocation | 20.00%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Percentage of actual 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/2009/role/commonPracticeRef -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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