Commitments and Contingencies, Environmental (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Environmental Contingency
Environmental accrual	$ 16.7	$ 16.7
Expected period related to remediation expenditures for environmental contingencies period		30 years
Potential increase in environmental costs	$ 11.6	$ 11.6
Time period within which Companys recorded estimate of its obligation may change	12 months
Minimum [Member]
Environmental Contingency
Period for final feasibility study		6 months
Maximum [Member]
Environmental Contingency
Period for final feasibility study		12 months

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Period For Final Feasibility Study

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

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The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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