Supplemental Balance Sheet Information (Components of Prepaid Expenses and Other) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
Prepaid taxes and tax refunds receivable	$ 145.0	$ 111.6
Receivables other than trade	69.2	67.2
Prepaid brochure costs, paper and other literature	14.9	64.8
Other	42.9	52.8
Prepaid expenses and other	$ 272.0	$ 296.4