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Commitments and Contingencies (Details) $ in Millions | Mar. 31, 2019 USD ($)
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Components of Environmental Loss Accrual [Abstract] |
Accrual For Environmental Loss Contingencies | $ 20
Accrued Environmental Loss Contingencies Current | 8
Federal Superfund and comparable state-managed sites | 3
Formerly owned or operated sites | 16
Owned or controlled sites at which Company operations have been discontinued | 1
Maximum |
Loss Contingency, Estimate [Abstract] |
Loss contingency maximum possible loss | $ 15

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