Supplemental Cash Flow Information (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Payments of interest and commitment fees	$ 138.3	$ 145.4
Interest paid, capitalized	1.4	2.9
Incurred liabilities for fixed and intangible asset additions	$ 26.5	$ 17.7

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

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