Other Current Assets - Level 4 Tag - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 88.1	$ 84.1
Other Receivables, Gross, Current	19.0	15.2
Income Taxes Receivable, Current	18.9	19.0
Other investments	55.8	30.7
Marketable securities (Note 2)	2.9	2.9
Contract assets	1.3	1.4
Deferred financing fees (Note 8)	0.5	0.5
Other	12.9	16.4
Total other current assets	$ 199.4	$ 170.2