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Other Commitments And Contingencies Other Commitments and Contingencies (Expense and Insurance Recoveries) (Details) - USD ($) $ in Millions | 3 Months Ended | 4 Months Ended | 9 Months Ended | 16 Months Ended | 25 Months Ended
--- | --- | --- | --- | --- | ---
Sep. 30, 2020 | Dec. 31, 2018 | Sep. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2020
Expense and Insurance Recoveries [Line Items] |  |  |  |  |
Third-party claims | $ (3) |  | $ (5) | $ 1,041 | $ 1,036
Other incident-related costs | 5 |  | 21 | 420 | 441
Total | 2 | $ 1,023 | 16 | 1,461 | 1,477
Insurance recoveries recorded | 0 |  | 0 | (800) | (800)
Total costs incurred | $ 2 |  | $ 16 | $ 661 | $ 677

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- Definition Costs Resulting from the Greater Lawrence Incident + References No definition available. + Details
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- Definition [Line Items] for Expense and Insurance Recoveries [Table] + References No definition available. + Details
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- Definition Greater Lawrence Incident Impact on Operation and Maintenance Expense + References No definition available. + Details
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- Definition The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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