STATEMENTS OF CHANGES IN CONSOLIDATED EQUITY - USD ($) $ in Millions	Total	[CommonStockMember]	Additional Paid-in Capital [Member]	[RetainedEarningsMember]	Treasury Stock	[AccumulatedOtherComprehensiveIncomeMember]	[NoncontrollingInterestMember]
Total Stockholders' Equity at Dec. 31, 2021	$ 832.7	$ 12.7	$ 1,596.7	$ 72.7	$ (4.8)	$ (991.7)	$ 147.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0.9			(7.1)			8.0
Other comprehensive income	73.8					82.8	(9.0)
Purchase of treasury stock	(89.9)				(89.9)
Conversion of convertible notes	82.5	0.3	45.4	(26.7)	63.5
Dividends paid to noncontrolling interest	(16.0)						(16.0)
Sale of subsidiary shares to noncontrolling interest	0.9						0.9
Employee stock plans	9.0	0.1	14.5	0.0	(5.6)
Total Stockholders' Equity at Jun. 30, 2022	893.9	13.1	1,656.6	38.9	(36.8)	(908.9)	131.0
Total Stockholders' Equity at Mar. 31, 2022	795.7	12.8	1,602.5	103.6	(99.7)	(960.5)	137.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(34.3)			(38.0)			3.7
Other comprehensive income	41.9					51.6	(9.7)
Conversion of convertible notes	82.5	0.3	45.4	(26.7)	63.5
Employee stock plans	8.1	0.0	8.7	0.0	(0.6)
Total Stockholders' Equity at Jun. 30, 2022	893.9	13.1	1,656.6	38.9	(36.8)	(908.9)	131.0
Total Stockholders' Equity at Dec. 31, 2022	1,157.2	13.1	1,668.1	176.9	(87.0)	(725.2)	111.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	151.3			146.1			5.2
Other comprehensive income	7.6					8.9	(1.3)
Purchase of treasury stock	(10.1)				(10.1)
Employee stock plans	3.2	0.1	13.9	0.0	(10.8)
Total Stockholders' Equity at Jun. 30, 2023	1,309.2	13.2	1,682.0	323.0	(107.9)	(716.3)	115.2
Total Stockholders' Equity at Mar. 31, 2023	1,214.3	13.2	1,675.1	247.0	(107.8)	(731.0)	117.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	79.1			76.0			3.1
Other comprehensive income	9.0					14.7	(5.7)
Employee stock plans	6.8	0.0	6.9	0.0	(0.1)
Total Stockholders' Equity at Jun. 30, 2023	$ 1,309.2	$ 13.2	$ 1,682.0	$ 323.0	$ (107.9)	$ (716.3)	$ 115.2