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Commitments And Contingencies (Narrative) (Details) $ in Millions | Sep. 30, 2021 USD ($) item
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Commitments and Contingencies [Line Items] |
Sites identified which we are or may be liable for remediation costs | 383
Sites subject of actions taken by the U.S. government | 28
Sites on the Superfund National Priorities List | 18
Personal Injury [Member] |
Commitments and Contingencies [Line Items] |
Percent of liability recorded related to asserted claims | 95.00%
Percent of liability recorded related to unasserted claims | 5.00%
Personal Injury [Member] | Minimum [Member] |
Commitments and Contingencies [Line Items] |
Reasonably possible outcome of related claims | $ | $ 303
Personal Injury [Member] | Maximum [Member] |
Commitments and Contingencies [Line Items] |
Reasonably possible outcome of related claims | $ | $ 333

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