Changes in Stockholders' Equity (Schedule of Stockholders' Equity) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	$ 3,443.8	$ 3,018.0
Stock compensation	7.0	6.8
Issuance of stock awards	(19.9)	(29.5)
SSARs exercised	(1.0)	(2.5)
Comprehensive income (loss):
Net income (loss)	137.0	151.4
Other comprehensive income (loss), net of reclassification adjustments:
Foreign currency translation adjustments	138.3	(47.3)
Defined benefit pension plans, net of tax	1.7	35.1
Deferred gains and losses on derivatives, net of tax	(3.3)	4.7
Payment of dividends to stockholders	(14.9)	(12.0)
Distributions to noncontrolling interest	(13.8)
Balance end of period	3,674.9	3,124.7
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	0.7	0.8
Other comprehensive income (loss), net of reclassification adjustments:
Balance end of period	0.7	0.8
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	3.9	30.9
Stock compensation	7.0	6.8
Issuance of stock awards	(7.0)	(29.5)
SSARs exercised	(1.0)	(2.5)
Other comprehensive income (loss), net of reclassification adjustments:
Balance end of period	2.9	5.7
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	5,182.2	4,759.1
Issuance of stock awards	(12.9)
Comprehensive income (loss):
Net income (loss)	151.8	150.8
Other comprehensive income (loss), net of reclassification adjustments:
Payment of dividends to stockholders	(14.9)	(12.0)
Balance end of period	5,306.2	4,897.9
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	(1,770.9)	(1,810.8)
Other comprehensive income (loss), net of reclassification adjustments:
Foreign currency translation adjustments	137.5	(46.9)
Defined benefit pension plans, net of tax	1.7	35.1
Deferred gains and losses on derivatives, net of tax	(3.3)	4.7
Balance end of period	(1,635.0)	(1,817.9)
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance beginning of period	27.9	38.0
Comprehensive income (loss):
Net income (loss)	(14.8)	0.6
Other comprehensive income (loss), net of reclassification adjustments:
Foreign currency translation adjustments	0.8	(0.4)
Distributions to noncontrolling interest	(13.8)
Balance end of period	$ 0.1	$ 38.2