Shareholders' Equity - Changes in Shareholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Increase (Decrease) in Stockholders' Equity
Net income (loss)	$ 16.5	$ 18.1
Other comprehensive loss	$ (12.7)	$ (8.4)
Cash dividends per share, declared (in dollars per share)	$ 0.28	$ 0.27
Total Shareholders' Equity
Increase (Decrease) in Stockholders' Equity
Beginning balance	$ 1,266.6	$ 1,078.5
Net income (loss)	16.2	18.0
Other comprehensive loss	(11.7)	(7.9)
Dividends	(5.8)	(5.7)
Incentive plan activity	(4.1)	1.2
Other	0.1	(3.2)
Ending balance	1,261.3	1,080.9
Common Stock
Increase (Decrease) in Stockholders' Equity
Beginning balance	$ 0.2	$ 0.2
Balance (in shares)	20.7	20.5
Incentive plan activity (in shares)	0.1	0.1
Ending balance	$ 0.2	$ 0.2
Balance (in shares)	20.8	20.6
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity
Beginning balance	$ 303.6	$ 289.6
Incentive plan activity	(4.1)	1.2
Other	0.1	(0.1)
Ending balance	299.6	290.7
Retained Earnings
Increase (Decrease) in Stockholders' Equity
Beginning balance	949.4	794.8
Net income (loss)	16.2	18.0
Dividends	(5.8)	(5.7)
Other		(3.1)
Ending balance	959.8	804.0
Accumulated Other Comprehensive Income
Increase (Decrease) in Stockholders' Equity
Beginning balance	14.6	(4.9)
Other comprehensive loss	(11.7)	(7.9)
Ending balance	2.9	(12.8)
Treasury Stock
Increase (Decrease) in Stockholders' Equity
Beginning balance	(1.2)	(1.2)
Ending balance	(1.2)	(1.2)
Redeemable Non-controlling Interests
Increase (Decrease) in Stockholders' Equity
Beginning balance	50.1	48.4
Net income (loss)	0.3	0.1
Other comprehensive loss	(1.0)	(0.5)
Other	(0.1)	3.2
Ending balance	$ 49.3	$ 51.2