Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Shares outstanding, beginning (in shares) at Dec. 31, 2022		74.8
Shareholders' equity, beginning at Dec. 31, 2022	$ 551.5	$ 0.0	$ 552.4	$ (0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	155.7		155.7
Issuance of common stock (in shares)		0.2
Taxes paid related to net share settlement of stock awards (in shares)		(0.1)
Taxes paid related to net share settlement of stock awards	(11.3)	$ (8.6)	(2.7)
Stock-based compensation	8.6	$ 8.6
Other	(0.3)		(0.3)
Shares outstanding, ending (in shares) at Mar. 31, 2023		74.9
Shareholders' equity, ending at Mar. 31, 2023	704.2	$ 0.0	705.1	(0.9)
Shares outstanding, beginning (in shares) at Dec. 31, 2022		74.8
Shareholders' equity, beginning at Dec. 31, 2022	551.5	$ 0.0	552.4	(0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	298.7
Shares outstanding, ending (in shares) at Jun. 30, 2023		74.9
Shareholders' equity, ending at Jun. 30, 2023	853.8	$ 8.0	846.7	(0.9)
Shares outstanding, beginning (in shares) at Mar. 31, 2023		74.9
Shareholders' equity, beginning at Mar. 31, 2023	704.2	$ 0.0	705.1	(0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	143.0		143.0
Taxes paid related to net share settlement of stock awards	(0.1)	(0.1)
Stock-based compensation	8.1	$ 8.1
Other	(1.4)		(1.4)
Shares outstanding, ending (in shares) at Jun. 30, 2023		74.9
Shareholders' equity, ending at Jun. 30, 2023	853.8	$ 8.0	846.7	(0.9)
Shares outstanding, beginning (in shares) at Dec. 31, 2023		74.5
Shareholders' equity, beginning at Dec. 31, 2023	893.6	$ 0.0	894.5	(0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	80.4		80.4
Issuance of common stock (in shares)		0.3
Repurchase of common stock (in shares)		(1.2)
Repurchase of common stock	(145.7)	$ (7.2)	(138.5)
Taxes paid related to net share settlement of stock awards (in shares)		(0.1)
Taxes paid related to net share settlement of stock awards	(7.6)		(7.6)
Stock-based compensation	7.2	$ 7.2
Other	(1.0)		(1.0)
Shares outstanding, ending (in shares) at Mar. 31, 2024		73.5
Shareholders' equity, ending at Mar. 31, 2024	826.9	$ 0.0	827.8	(0.9)
Shares outstanding, beginning (in shares) at Dec. 31, 2023		74.5
Shareholders' equity, beginning at Dec. 31, 2023	893.6	$ 0.0	894.5	(0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	289.7
Shares outstanding, ending (in shares) at Jun. 30, 2024		73.4
Shareholders' equity, ending at Jun. 30, 2024	1,030.9	$ 0.0	1,031.9	(1.0)
Shares outstanding, beginning (in shares) at Mar. 31, 2024		73.5
Shareholders' equity, beginning at Mar. 31, 2024	826.9	$ 0.0	827.8	(0.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	209.3		209.3
Repurchase of common stock (in shares)		(0.1)
Repurchase of common stock	(13.0)	$ (8.9)	(4.1)
Taxes paid related to net share settlement of stock awards	(0.2)		(0.2)
Stock-based compensation	8.9	$ 8.9
Other	(1.0)		(0.9)	(0.1)
Shares outstanding, ending (in shares) at Jun. 30, 2024		73.4
Shareholders' equity, ending at Jun. 30, 2024	$ 1,030.9	$ 0.0	$ 1,031.9	$ (1.0)