Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Additional Paid in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance at Dec. 31, 2022	$ 3,667.1	$ 0.9	$ 581.8	$ 3,186.8	$ (102.4)
Beginning Balance (in shares) at Dec. 31, 2022		89,695
Common stock repurchases and retirements (in shares)		(286)
Common stock repurchases and retirements	(41.5)		(2.5)	(39.0)
Common stock withheld and retired to cover taxes on vested stock awards	(15.7)		(1.1)	(14.6)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(121)
Common stock dividends declared	(338.7)			(338.7)
Share-based compensation and other	34.3		34.3
Share-based compensation and other (in shares)		337
Comprehensive income	581.7			576.0	5.7
Ending Balance at Sep. 30, 2023	3,887.2	$ 0.9	612.5	3,370.5	(96.7)
Ending Balance (in shares) at Sep. 30, 2023		89,625
Beginning Balance at Jun. 30, 2023	3,848.6	$ 0.9	607.4	3,339.0	(98.7)
Beginning Balance (in shares) at Jun. 30, 2023		89,916
Common stock repurchases and retirements (in shares)		(286)
Common stock repurchases and retirements	(41.5)		(2.5)	(39.0)
Common stock withheld and retired to cover taxes on vested stock awards	(0.2)			(0.2)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(1)
Common stock dividends declared	(112.5)			(112.5)
Share-based compensation and other	7.6		7.6
Share-based compensation and other (in shares)		(4)
Comprehensive income	185.2			183.2	2.0
Ending Balance at Sep. 30, 2023	3,887.2	$ 0.9	612.5	3,370.5	(96.7)
Ending Balance (in shares) at Sep. 30, 2023		89,625
Beginning Balance at Dec. 31, 2023	3,997.3	$ 0.9	620.1	3,447.2	(70.9)
Beginning Balance (in shares) at Dec. 31, 2023		89,625
Common stock withheld and retired to cover taxes on vested stock awards	(24.8)		(1.3)	(23.5)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(139)
Common stock dividends declared	(338.6)			(338.6)
Share-based compensation and other	41.8		41.8
Share-based compensation and other (in shares)		323
Comprehensive income	587.9			584.0	3.9
Ending Balance at Sep. 30, 2024	4,263.6	$ 0.9	660.6	3,669.1	(67.0)
Ending Balance (in shares) at Sep. 30, 2024		89,809
Beginning Balance at Jun. 30, 2024	4,126.6	$ 0.9	650.3	3,544.4	(69.0)
Beginning Balance (in shares) at Jun. 30, 2024		89,815
Common stock withheld and retired to cover taxes on vested stock awards	(0.7)		0.0	(0.7)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(4)
Common stock dividends declared	(112.7)			(112.7)
Share-based compensation and other	10.3		10.3
Share-based compensation and other (in shares)		(2)
Comprehensive income	240.1			238.1	2.0
Ending Balance at Sep. 30, 2024	$ 4,263.6	$ 0.9	$ 660.6	$ 3,669.1	$ (67.0)
Ending Balance (in shares) at Sep. 30, 2024		89,809