Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss	Defined Benefit Pension Plans	Cumulative Translation Adjustment	Deferred Gains (Losses) on Derivatives	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2020			74,962,231
Stockholders' equity, beginning of period at Dec. 31, 2020	$ 3,018.0		$ 0.8	$ 30.9	$ 4,759.1		$ (1,810.8)	$ (313.3)	$ (1,495.0)	$ (2.5)	$ 38.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	901.5				897.0						4.5
Payment of dividends to shareholders	(358.5)				(358.5)
Issuance of non-employee director restricted stock (in shares)			8,912
Issuance of non-employee director restricted stock	1.3			1.3
Issuance of stock awards (in shares)			362,034
Issuance of stock awards	(29.5)			(29.5)
SSARs exercised (in shares)			60,339
SSARs exercised	(5.4)			(5.4)
Stock compensation	26.1			26.1
Distribution to noncontrolling interest	(3.6)										(3.6)
Sale of noncontrolling interests	(10.6)										(10.6)
Purchases and retirement of common stock (in shares)			(952,204)
Purchases and retirement of common stock	(135.0)		$ (0.1)	(19.5)	(115.4)
Defined benefit pension plans, net of taxes:
Prior service (cost) credit arising during the year	10.0						10.0	10.0
Net (gain) loss recognized due to settlement	0.1						0.1	0.1
Net loss recognized due to curtailment	6.3						6.3	6.3
Net actuarial gain (loss) arising during year	53.6						53.6	53.6
Amortization of prior service cost (credit) included in net periodic pension cost	0.6						0.6	0.6
Amortization of net actuarial losses included in net periodic pension cost	12.3						12.3	12.3
Deferred gains and losses on derivatives, net	2.1						2.1			2.1
Change in cumulative translation adjustment	(45.5)						(45.1)		(45.1)		(0.4)
Ending balance (in shares) at Dec. 31, 2021			74,441,312
Stockholders' equity, end of period at Dec. 31, 2021	3,443.8		$ 0.7	3.9	5,182.2		(1,770.9)	(230.4)	(1,540.1)	(0.4)	27.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	874.7				889.6						(14.9)
Payment of dividends to shareholders	(404.3)				(404.3)
Issuance of non-employee director restricted stock (in shares)			10,301
Issuance of non-employee director restricted stock	1.5			1.5
Issuance of stock awards (in shares)			250,719
Issuance of stock awards	(19.4)			(6.5)	(12.9)
SSARs exercised (in shares)			12,307
SSARs exercised	(1.2)			(1.2)
Stock compensation	32.5			32.5
Distribution to noncontrolling interest	(13.8)										(13.8)
Investment by noncontrolling interests	0.1										0.1
Purchases and retirement of common stock (in shares)			(113,824)
Defined benefit pension plans, net of taxes:
Prior service (cost) credit arising during the year	(19.1)						(19.1)	(19.1)
Net (gain) loss recognized due to settlement	(0.4)						(0.4)	(0.4)
Net loss recognized due to curtailment	0.0
Net actuarial gain (loss) arising during year	12.3						12.3	12.3
Amortization of prior service cost (credit) included in net periodic pension cost	0.0
Amortization of net actuarial losses included in net periodic pension cost	6.4						6.4	6.4
Deferred gains and losses on derivatives, net	(0.5)						(0.5)			(0.5)
Change in cumulative translation adjustment	(30.0)						(30.9)		(30.9)		0.9
Ending balance (in shares) at Dec. 31, 2022			74,600,815
Stockholders' equity, end of period at Dec. 31, 2022	$ 3,882.6	$ (5.5)	$ 0.7	30.2	5,654.6	$ (5.5)	(1,803.1)	(231.2)	(1,571.0)	(0.9)	0.2
Defined benefit pension plans, net of taxes:
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2016-13 [Member]
Net income (loss)	$ 1,171.3				1,171.4						(0.1)
Payment of dividends to shareholders	(457.4)				(457.4)
Issuance of non-employee director restricted stock (in shares)			10,524
Issuance of non-employee director restricted stock	1.5			1.5
Issuance of stock awards (in shares)			256,709
Issuance of stock awards	(20.5)			(20.5)	0.0
SSARs exercised (in shares)			21,594
SSARs exercised	(2.1)			(2.1)
Stock compensation	44.9			44.9
Purchases and retirement of common stock (in shares)			(371,669)
Purchases and retirement of common stock	(53.0)			(49.9)	(3.1)
Prior service (cost) credit arising during the year	0.0
Net (gain) loss recognized due to settlement	0.4						0.4	0.4
Net loss recognized due to curtailment	0.0
Net actuarial gain (loss) arising during year	(16.1)						(16.1)	(16.1)
Amortization of prior service cost (credit) included in net periodic pension cost	1.3						1.3	1.3
Amortization of net actuarial losses included in net periodic pension cost	7.0						7.0	7.0
Deferred gains and losses on derivatives, net	0.1						0.1			0.1
Change in cumulative translation adjustment	102.3						102.3		102.3		0.0
Ending balance (in shares) at Dec. 31, 2023			74,517,973
Stockholders' equity, end of period at Dec. 31, 2023	$ 4,656.8		$ 0.7	$ 4.1	$ 6,360.0		$ (1,708.1)	$ (238.6)	$ (1,468.7)	$ (0.8)	$ 0.1