Consolidated Statements of Equity (unaudited) - USD ($) $ in Millions	Total	Common Stock and Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance at Dec. 31, 2018	$ 337.0	$ 481.8	$ 676.7	$ (895.5)	$ 67.9	$ 6.1
Increase (Decrease) in Stockholders' Equity
Net income	24.6	0.0	24.7	0.0	0.0	(0.1)
Repurchase of common stock	(4.8)	0.0	0.0	(4.8)	0.0	0.0
Cash paid for repurchases of common stock	4.8
Payments in consideration of employee tax obligations related to stock-based compensation	(4.3)	(4.3)	0.0	0.0	0.0	0.0
Stock-based compensation	1.9	1.9	0.0	0.0	0.0	0.0
Exercise of stock options	9.2	(2.2)	0.0	11.4	0.0	0.0
Shares issued	(0.3)	(7.4)	0.0	7.1	0.0	0.0
Dividends declared	(18.1)	0.0	(18.1)	0.0	0.0	0.0
Other comprehensive (loss) income	8.6	0.0	0.0	0.0	8.6	0.0
Ending balance at Mar. 31, 2019	353.8	469.8	683.3	(881.8)	76.5	6.0
Beginning balance at Dec. 31, 2019	402.2	478.6	730.5	(892.2)	78.8	6.5
Increase (Decrease) in Stockholders' Equity
Net income	42.1	0.0	42.0	0.0	0.0	0.1
Repurchase of common stock	(40.4)	0.0	0.0	(40.4)	0.0	0.0
Cash paid for repurchases of common stock	40.4
Payments in consideration of employee tax obligations related to stock-based compensation	(4.1)	(4.1)	0.0	0.0	0.0	0.0
Stock-based compensation	2.9	2.9	0.0	0.0	0.0	0.0
Shares issued	0.0	(10.3)	0.0	10.3	0.0	0.0
Dividends declared	(20.2)	0.0	(20.2)	0.0	0.0	0.0
Other comprehensive (loss) income	1.4	0.0	0.0	0.0	1.4	0.0
Ending balance at Mar. 31, 2020	$ 383.9	$ 467.1	$ 752.3	$ (922.3)	$ 80.2	$ 6.6