Fair Value Measurements and Risk - Carrying Amounts and Fair Values of Debt (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		$ 1,546.5		$ 1,543.9
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other borrowings		52.5		55.1
Total debt		1,573.0		1,608.5
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other borrowings		52.5		55.1
Total debt		1,546.5		1,543.9
Term Loan B (USD)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		4.1		4.3
Term Loan B (USD) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		403.8		409.7
Term Loan B (USD) | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[1]	404.3		404.1
Term Loan B (EUR)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		0.9		1.0
Term Loan B (EUR) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		98.3		93.7
Term Loan B (EUR) | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[1]	98.4		94.0
5.125% Senior Notes, Due 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		5.4		5.8
Total debt		$ 694.6		$ 694.2
Interest rate (percent)		5.125%		5.125%
5.125% Senior Notes, Due 2021 | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		$ 712.8		$ 728.7
5.125% Senior Notes, Due 2021 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[2]	694.6		694.2
5.625% Senior Notes, Due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		3.3		3.5
Total debt		$ 296.7		$ 296.5
Interest rate (percent)		5.625%		5.625%
5.625% Senior Notes, Due 2024 | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		$ 305.6		$ 321.3
5.625% Senior Notes, Due 2024 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[2]	296.7		$ 296.5
Net Investment Hedging
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		$ 0.0	$ 0.0

[1] (2)Carrying amounts are net of unamortized debt issuance costs and discounts of $4.1 million and $0.9 million as of March 31, 2018, and $4.3 million and $1.0 million as of December 31, 2017, related to the U.S. dollar term loan and euro term loan, respectively.

[2] (1)Carrying amounts are net of unamortized debt issuance costs of $5.4 million and $3.3 million as of March 31, 2018, and $5.8 million and $3.5 million as of December 31, 2017, related to the 5.125% senior notes due 2021 and 5.625% senior notes due 2024, respectively.