CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Treasury Stock, at Cost
Beginning balance (in shares) at Dec. 31, 2023		220.5
Beginning balance at Dec. 31, 2023	$ (154.5)	$ 2.2	$ 2,638.2	$ 60.3	$ (2,824.2)	$ (31.0)
Beginning balance (in shares) at Dec. 31, 2023						3.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and release of stock awards, net of shares withheld (in shares)		7.9
Exercise of stock options and release of stock awards, net of shares withheld	(3.4)	$ 0.1	(3.5)
Issuance of shares from Employee Stock Purchase Plans (in shares)		0.3
Issuance of shares from Employee Stock Purchase Plan	0.4		0.4
Share-based compensation expense for equity classified awards	26.0		26.0
Net income (loss)	(615.6)				(615.6)
Other comprehensive (loss) income	(9.1)			(9.1)
Ending balance (in shares) at Jun. 30, 2024		228.7
Ending balance at Jun. 30, 2024	(756.2)	$ 2.3	2,661.1	51.2	(3,439.8)	$ (31.0)
Ending balance (in shares) at Jun. 30, 2024						3.1
Beginning balance (in shares) at Mar. 31, 2024		226.6
Beginning balance at Mar. 31, 2024	(787.2)	$ 2.3	2,647.7	58.6	(3,464.8)	$ (31.0)
Beginning balance (in shares) at Mar. 31, 2024						3.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and release of stock awards, net of shares withheld (in shares)		1.8
Issuance of shares from Employee Stock Purchase Plans (in shares)		0.3
Issuance of shares from Employee Stock Purchase Plan	0.4		0.4
Share-based compensation expense for equity classified awards	13.0		13.0
Net income (loss)	25.0				25.0
Other comprehensive (loss) income	(7.4)			(7.4)
Ending balance (in shares) at Jun. 30, 2024		228.7
Ending balance at Jun. 30, 2024	$ (756.2)	$ 2.3	2,661.1	51.2	(3,439.8)	$ (31.0)
Ending balance (in shares) at Jun. 30, 2024						3.1
Beginning balance (in shares) at Dec. 31, 2024	229.1	232.2
Beginning balance at Dec. 31, 2024	$ (1,004.2)	$ 2.3	2,682.8	24.1	(3,682.4)	$ (31.0)
Beginning balance (in shares) at Dec. 31, 2024	3.1					3.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and release of stock awards, net of shares withheld (in shares)		9.6
Exercise of stock options and release of stock awards, net of shares withheld	$ (0.8)	$ 0.1	(0.9)
Issuance of shares from Employee Stock Purchase Plans (in shares)		0.3
Issuance of shares from Employee Stock Purchase Plan	0.3		0.3
Share-based compensation expense for equity classified awards	14.5		14.5
Net income (loss)	(126.0)				(126.0)
Other comprehensive (loss) income	$ (2.8)			(2.8)
Ending balance (in shares) at Jun. 30, 2025	239.0	242.1
Ending balance at Jun. 30, 2025	$ (1,119.0)	$ 2.4	2,696.7	21.3	(3,808.4)	$ (31.0)
Ending balance (in shares) at Jun. 30, 2025	3.1					3.1
Beginning balance (in shares) at Mar. 31, 2025		240.4
Beginning balance at Mar. 31, 2025	$ (1,073.1)	$ 2.4	2,690.3	19.1	(3,753.9)	$ (31.0)
Beginning balance (in shares) at Mar. 31, 2025						3.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and release of stock awards, net of shares withheld (in shares)		1.4
Exercise of stock options and release of stock awards, net of shares withheld	(0.8)		(0.8)
Issuance of shares from Employee Stock Purchase Plans (in shares)		0.3
Issuance of shares from Employee Stock Purchase Plan	0.3		0.3
Share-based compensation expense for equity classified awards	6.9		6.9
Net income (loss)	(54.5)				(54.5)
Other comprehensive (loss) income	$ 2.2			2.2
Ending balance (in shares) at Jun. 30, 2025	239.0	242.1
Ending balance at Jun. 30, 2025	$ (1,119.0)	$ 2.4	$ 2,696.7	$ 21.3	$ (3,808.4)	$ (31.0)
Ending balance (in shares) at Jun. 30, 2025	3.1					3.1