Condensed Consolidated Statements of Stockholders’ Equity (Unaudited) - USD ($) shares in Millions, $ in Millions		Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Shares in Treasury
Balance at beginning (in shares) at Dec. 31, 2020			52.9
Balance at the beginning of the period at Dec. 31, 2020		$ 2,537.7	$ 78.7	$ 441.7	$ (97.0)	$ 3,928.7	$ (1,814.4)
Balance at beginning (in shares) at Dec. 31, 2020							25.5
Increase (Decrease) in Shareholders' Equity
Net income		293.6				293.6
Other comprehensive income (loss), net of tax		(4.2)			(4.2)
Dividends		(84.4)				(84.4)
Repurchases of common stock (in shares)			(1.7)				(1.7)
Repurchases of common stock		(290.6)					$ (290.6)
Issuances and deferrals, net for stock-based compensation (in shares)	[1]		(0.9)				(0.9)
Issuances and deferrals. net for stock-based compensation	[1]	92.7		32.1			$ 60.6
Balance at ending (in shares) at Sep. 30, 2021			52.1
Balance at the end of the period at Sep. 30, 2021		2,544.8	$ 78.7	473.8	(101.2)	4,137.9	$ (2,044.4)
Balance at ending (in shares) at Sep. 30, 2021							26.3
Balance at beginning (in shares) at Jun. 30, 2021			51.9
Balance at the beginning of the period at Jun. 30, 2021		2,417.9	$ 78.7	460.1	(102.8)	4,024.2	$ (2,042.3)
Balance at beginning (in shares) at Jun. 30, 2021							26.5
Increase (Decrease) in Shareholders' Equity
Net income		142.1				142.1
Other comprehensive income (loss), net of tax		1.6			1.6
Dividends		(28.4)				(28.4)
Repurchases of common stock (in shares)			(0.1)				(0.1)
Repurchases of common stock		(25.0)					$ (25.0)
Issuances and deferrals, net for stock-based compensation (in shares)	[1]		(0.3)				(0.3)
Issuances and deferrals. net for stock-based compensation	[1]	36.6		13.7			$ 22.9
Balance at ending (in shares) at Sep. 30, 2021			52.1
Balance at the end of the period at Sep. 30, 2021		$ 2,544.8	$ 78.7	473.8	(101.2)	4,137.9	$ (2,044.4)
Balance at ending (in shares) at Sep. 30, 2021							26.3
Balance at beginning (in shares) at Dec. 31, 2021		52.0	52.0
Balance at the beginning of the period at Dec. 31, 2021		$ 2,629.5	$ 78.7	481.5	(105.2)	4,237.7	$ (2,063.2)
Balance at beginning (in shares) at Dec. 31, 2021		26.4					26.4
Increase (Decrease) in Shareholders' Equity
Net income		$ 749.8				749.8
Other comprehensive income (loss), net of tax		(84.2)			(84.2)
Dividends		(95.8)				(95.8)
Repurchases of common stock (in shares)			(0.8)				(0.8)
Repurchases of common stock		(205.2)					$ (205.2)
Issuances and deferrals, net for stock-based compensation (in shares)	[1]		(0.4)				(0.4)
Issuances and deferrals. net for stock-based compensation	[1]	$ 47.6		21.1			$ 26.5
Balance at ending (in shares) at Sep. 30, 2022		51.6	51.6
Balance at the end of the period at Sep. 30, 2022		$ 3,041.7	$ 78.7	502.6	(189.4)	4,891.7	$ (2,241.9)
Balance at ending (in shares) at Sep. 30, 2022		26.8					26.8
Balance at beginning (in shares) at Jun. 30, 2022			51.5
Balance at the beginning of the period at Jun. 30, 2022		$ 2,875.1	$ 78.7	490.9	(142.2)	4,676.1	$ (2,228.4)
Balance at beginning (in shares) at Jun. 30, 2022							26.9
Increase (Decrease) in Shareholders' Equity
Net income		254.7				254.7
Other comprehensive income (loss), net of tax		(47.2)			(47.2)
Dividends		(39.1)				(39.1)
Repurchases of common stock (in shares)			(0.1)				(0.1)
Repurchases of common stock		(30.2)					$ (30.2)
Issuances and deferrals, net for stock-based compensation (in shares)	[2]		(0.2)				(0.2)
Issuances and deferrals. net for stock-based compensation	[2]	$ 28.4		11.7			$ 16.7
Balance at ending (in shares) at Sep. 30, 2022		51.6	51.6
Balance at the end of the period at Sep. 30, 2022		$ 3,041.7	$ 78.7	$ 502.6	$ (189.4)	$ 4,891.7	$ (2,241.9)
Balance at ending (in shares) at Sep. 30, 2022		26.8					26.8

[1] Issuances and deferrals, net for stock-based compensation reflects share activity related to option exercises, restricted and performance shares vested, and net issuances and deferrals associated with deferred compensation equity.

[2] Issuances and deferrals, net for stock-based compensation reflects share activity related to option exercises, restricted and performance shares vested, and net issuances and deferrals associated with deferred compensation equity.