Stockholders' Equity (Schedule of Stockholders' Equity) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2022
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance beginning of period	$ 504.7		$ 0.0
Net income (loss)	(1.1)		(2.9)
Foreign currency translation adjustments	1.1		0.1
Initial fair value of redeemable noncontrolling interests (Note 2)			332.2
Redeemable noncontrolling interests measurement period adjustment (Note 2)	(167.2)
Investment by redeemable noncontrolling interest (Note 2)			8.1
Balance end of period	337.5		337.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	4,053.9	$ 4,139.0	4,656.8	$ 3,882.6
Stock compensation	3.8	10.2	18.6	37.5
Issuance of stock awards	(0.7)	(0.3)	(13.8)	(20.5)
SSARs exercised			(0.1)	(1.2)
Sale of minority interest	(0.1)		0.1
Comprehensive income:
Net income (loss)	30.0		(169.1)
Net income	28.9	280.5	(172.0)	832.3
Other comprehensive income (loss):
Foreign currency translation adjustments	79.9		(107.2)
Foreign currency translation adjustments	81.0	(54.5)	(107.1)	64.1
Defined pension and postretirement benefit plans, net of tax	2.0	1.9	5.6	5.6
Deferred gains and losses on derivatives, net of tax	1.6	0.5	6.5	(3.5)
Payment of dividends to stockholders	(21.6)	(21.7)	(251.5)	(435.8)
Equity transaction associated with JCA noncontrolling interest (Note 2)			3.1
Balance end of period	4,148.8	4,355.6	4,148.8	4,355.6	$ 3,882.6
Accounting Standards Update [Extensible Enumeration]					Accounting Standards Update 2016-13 [Member]
Cumulative Effect, Period of Adoption, Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period				(5.5)
Other comprehensive income (loss):
Balance end of period					$ (5.5)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	0.7	0.7	0.7	0.7
Other comprehensive income (loss):
Balance end of period	0.7	0.7	0.7	0.7	0.7
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	9.2	36.1	4.1	30.2
Stock compensation	3.8	10.2	18.6	37.5
Issuance of stock awards	(0.6)	(0.3)	(13.3)	(20.5)
SSARs exercised			(0.1)	(1.2)
Other comprehensive income (loss):
Equity transaction associated with JCA noncontrolling interest (Note 2)			3.1
Balance end of period	12.4	46.0	12.4	46.0	30.2
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	5,930.6	5,786.8	6,360.0	5,654.6
Issuance of stock awards	(0.1)		(0.5)
Comprehensive income:
Net income (loss)	30.0		(169.1)
Net income		280.6		832.4
Other comprehensive income (loss):
Payment of dividends to stockholders	(21.6)	(21.7)	(251.5)	(435.8)
Balance end of period	5,938.9	6,045.7	5,938.9	6,045.7	5,654.6
Retained Earnings | Cumulative Effect, Period of Adoption, Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period				(5.5)
Other comprehensive income (loss):
Balance end of period					(5.5)
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	(1,886.7)	(1,684.8)	(1,708.1)	(1,803.1)
Other comprehensive income (loss):
Foreign currency translation adjustments	79.9		(107.2)
Foreign currency translation adjustments		(54.5)		64.1
Defined pension and postretirement benefit plans, net of tax	2.0	1.9	5.6	5.6
Deferred gains and losses on derivatives, net of tax	1.6	0.5	6.5	(3.5)
Balance end of period	(1,803.2)	(1,736.9)	(1,803.2)	(1,736.9)	(1,803.1)
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	0.1	0.2	0.1	0.2
Sale of minority interest	(0.1)		0.1
Comprehensive income:
Net income		(0.1)		(0.1)
Other comprehensive income (loss):
Balance end of period	$ 0.0	$ 0.1	$ 0.0	$ 0.1	$ 0.2