Prepaid Expenses and Other (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Prepaid Expense and Other Assets [Abstract]
Prepaid expenses	$ 64.0	$ 72.5
Mobile airtime inventory	5.8	4.8
Income tax receivable	37.6	21.1
Other	20.1	20.6
Prepaid expenses and other	$ 127.5	$ 119.0