Supplemental Cash Flow Information (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	$ 140.2	$ 58.6
Income Taxes Paid, Net	15.3	3.1
Capital Expenditures Incurred but Not yet Paid	55.9	25.0
Insurance prepayment financed [Member]
Liabilities Assumed	$ 7.2	$ 6.1

Future cash outflow to pay for purchases of fixed assets that have occurred.

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