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, 2020	$ 3,246.3	$ 0.9	$ 554.4	$ 2,835.5	$ (144.5)
Beginning Balance (in shares) at Dec. 31, 2020		94,830
Common stock repurchases and retirements	(193.0)		(11.5)	(181.5)
Common stock repurchases and retirements (in shares)		(1,443)
Common stock withheld and retired to cover taxes on vested stock awards	(12.9)		(0.8)	(12.1)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(95)
Common stock dividends declared	(379.9)			(379.9)
Share-based compensation and other	36.3		37.3	(1.0)
Share-based compensation expense and other (in shares)		247
Comprehensive income	910.4			841.1	69.3
Ending Balance at Dec. 31, 2021	3,607.2	$ 0.9	579.4	3,102.1	(75.2)
Ending Balance (in shares) at Dec. 31, 2021		93,539
Common stock repurchases and retirements	(522.6)		(33.5)	(489.1)
Common stock repurchases and retirements (in shares)		(4,035)
Common stock withheld and retired to cover taxes on vested stock awards	(15.4)		(0.9)	(14.5)
Common stock withheld and retired to cover taxes on vested stock awards (in shares)		(111)
Common stock dividends declared	(441.2)			(441.2)
Share-based compensation and other	36.5		36.8	(0.3)
Share-based compensation expense and other (in shares)		302
Comprehensive income	1,002.6			1,029.8	(27.2)
Ending Balance at Dec. 31, 2022	3,667.1	$ 0.9	581.8	3,186.8	(102.4)
Ending Balance (in shares) at Dec. 31, 2022		89,695
Common stock repurchases and retirements	(41.5)		(2.5)	(39.0)
Common stock repurchases and retirements (in shares)		(286)
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	(451.2)			(451.2)
Share-based compensation and other	41.9		41.9
Share-based compensation expense and other (in shares)		337
Comprehensive income	796.7			765.2	31.5
Ending Balance at Dec. 31, 2023	$ 3,997.3	$ 0.9	$ 620.1	$ 3,447.2	$ (70.9)
Ending Balance (in shares) at Dec. 31, 2023		89,625