Financing Arrangements - Components of Long-Term Debt (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal Amount	$ 1,240.6	$ 1,242.8
Unamortized discount and debt issuance cost	12.7	13.5
Long-term Debt, Total	1,227.9	1,229.3
Less short-term and current portion of long-term debt, Principal Amount	18.2	18.4
Less short-term and current portion of long-term debt, Unamortized discount and debt issuance cost	0.0	0.0
Less short-term and current portion of long-term debt	18.2	18.4
Total long-term debt, gross, net of current	1,222.4	1,224.4
Debt excluding current, unamortized discount and debt issuance costs	12.7	13.5
Total long-term debt, net of current portion	1,209.7	1,210.9
Senior secured revolving credit facility due 2022 | Revolving Credit Facility
Debt Instrument [Line Items]
Principal Amount	0.0	0.0
Unamortized discount and debt issuance cost	0.0	0.0
Long-term Debt, Total	$ 0.0	$ 0.0
Weighted average interest rate	0.00%	3.90%
Senior secured term loan due 2026 | Secured Debt
Debt Instrument [Line Items]
Principal Amount	$ 622.9	$ 624.5
Unamortized discount and debt issuance cost	9.3	9.8
Long-term Debt, Total	$ 613.6	$ 614.7
Weighted average interest rate	3.35%	4.01%
5.25% Senior Notes Due 2023 | Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	5.25%	5.25%
Principal Amount	$ 600.0	$ 600.0
Unamortized discount and debt issuance cost	3.4	3.7
Long-term Debt, Total	$ 596.6	$ 596.3
Weighted average interest rate	5.25%	5.25%
Other Debt
Debt Instrument [Line Items]
Principal Amount	$ 17.7	$ 18.3
Unamortized discount and debt issuance cost	0.0	0.0
Long-term Debt, Total	$ 17.7	$ 18.3