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Other Expense (Income) - Restructuring and Related Charges (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Severance and benefits
Restructuring Reserve [Roll Forward]
Balance, December 31, 2019			$ 1.4
Cash payments			(1.0)
Balance, June 30, 2020	$ 0.4		0.4
Asset-related charges
Restructuring Reserve [Roll Forward]
Cash payments			0.0
Other charges
Restructuring Reserve [Roll Forward]
Cash payments			0.0
2018 Restructuring Plan
Restructuring and related charges:
Restructuring and related cost, expected cost					$ 16.0
Restructuring and related cost, cumulative cost incurred					$ 13.7
Total restructuring and related charges	0.0	$ 1.4	0.0	$ 2.0
Severance and post-employment benefits	0.0	1.3	0.0	1.6
Other charges	0.0	$ 0.1	0.0	$ 0.4
Restructuring Reserve [Roll Forward]
Balance, December 31, 2019			1.4
Cash payments			(1.0)
Balance, June 30, 2020	0.4		0.4
2018 Restructuring Plan \| Asset-related charges
Restructuring Reserve [Roll Forward]
Balance, December 31, 2019			0.0
Balance, June 30, 2020	0.0		0.0
2018 Restructuring Plan \| Other charges
Restructuring Reserve [Roll Forward]
Balance, December 31, 2019			0.0
Balance, June 30, 2020	$ 0.0		$ 0.0