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Other Commitments and Contingencies (Expense Incurred and Insurance Recoveries) (Details) - USD ($) $ in Millions | 4 Months Ended | 12 Months Ended | 16 Months Ended | 28 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2020
Expense and Insurance Recoveries [Line Items] |  |  |  |
Third-Party Claims, fines, penalties, and settlements |  | $ (5.0) | $ 1,041.0 | $ 1,036.0
Other incident-related costs |  | 22.0 | 420.0 | 442.0
Total | $ 1,023.0 | 17.0 | 1,461.0 | 1,478.0
Insurance Recoveries |  | 0.0 | (800.0) | (800.0)
Impact to income (loss) before income taxes |  | $ 17.0 | $ 661.0 | $ 678.0

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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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