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Commitments and Contingencies (Details) $ in Millions, $ in Millions	3 Months Ended				12 Months Ended
	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 CAD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Loss Contingency, Damages Sought, Value				$ 10.0
Income Tax Examination, Estimate of Possible Loss			$ 37.4
Income Tax Examination, Penalties Accrued			$ 37.4
Income Tax Examination, Interest Expense	$ 0.5	$ 0.5
Taxes Payable	7.0
Income Tax Examination, Penalties and Interest Expense	$ 31.0
IRS-Walter Energy Claim 1 [Member]
Loss Contingency, Estimate of Possible Loss								$ 554.3
IRS-Walter Energy Claim 1 Priority [Member]
Loss Contingency, Estimate of Possible Loss							$ 229.1
IRS-Walter Energy Claim 2 [Member]
Loss Contingency, Estimate of Possible Loss							860.4
IRS-Walter Energy Claim 2 Priority [Member]
Loss Contingency, Estimate of Possible Loss							$ 535.3
Product Concentration Risk [Member]
Operating Leases
Product Warranty Expense					$ 14.1	$ 9.8

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Estimated amount of loss resulting from an adverse tax position.

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