Contingent Liabilities and Commitments (Details) - Environmental assessment and remediation [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Site Contingency [Line Items]
Environmental assessment and remediation costs, best estimate	$ 1.9
Accrued environmental assessment and remediation costs, total	1.9	$ 2.0
Accrued environmental assessment and remediation costs, current	1.3	1.3
Accrued environmental assessment and remediation costs, noncurrent	$ 0.6	$ 0.7

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

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