Contingent Liabilities and Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Environmental Matters
Environmental assessment and remediation costs, undiscounted	$ 2.0
Accrued environmental liabilities	2.0	$ 3.0
Accrued Environmental Loss Contingencies, Current	1.3	1.3
Accrued Environmental Loss Contingencies, Noncurrent	$ 0.7	$ 1.7

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Undiscounted amount of the accrual for environmental loss contingencies.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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