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Debt - Convertible Senior Notes (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2025 USD ($) $ / shares	Jun. 30, 2024 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2025 USD ($) d $ / shares	Jun. 30, 2024 USD ($)
Debt Instrument [Line Items]
Proceeds from convertible debt			$ 1,400.0
Convertible Scenario One
Debt Instrument [Line Items]
Convertible debt, threshold trading days \| d				20
Convertible debt, threshold consecutive trading days \| d				30
Convertible debt, threshold percentage of stock price trigger				130.00%
Convertible Scenario Two
Debt Instrument [Line Items]
Convertible debt, threshold trading days \| d				5
Convertible debt, threshold consecutive trading days \| d				5
Convertible debt, threshold percentage of stock price trigger				98.00%
Convertible Scenario Three
Debt Instrument [Line Items]
Convertible debt, threshold trading days \| d				20
Convertible debt, threshold consecutive trading days \| d				30
Convertible debt, threshold percentage of stock price trigger				130.00%
Convertible Debt \| Convertible Scenario Three
Debt Instrument [Line Items]
Convertible debt, redemption percentage				100.00%
Convertible Debt \| Convertible Scenario Four
Debt Instrument [Line Items]
Convertible debt, redemption percentage				100.00%
2026 Notes
Debt Instrument [Line Items]
Convertible debt, conversion rate				0.0261458
Convertible debt, conversion rate (in dollars per share) \| $ / shares	$ 38.25			$ 38.25
Interest expense	$ 0.5	$ 0.6		$ 1.1	$ 1.1
2026 Notes \| Maximum
Debt Instrument [Line Items]
Convertible debt, conversion rate				0.0431406
2026 Notes \| Convertible Debt
Debt Instrument [Line Items]
Proceeds from convertible debt			695.8
Debt issuance costs	$ 11.0			$ 11.0
Debt instrument, term				5 years
Effective interest rate	0.32%			0.32%
2028 Notes
Debt Instrument [Line Items]
Convertible debt, conversion rate				0.0282889
Convertible debt, conversion rate (in dollars per share) \| $ / shares	$ 35.35			$ 35.35
Interest expense	$ 0.4	$ 0.4		$ 0.7	$ 0.8
2028 Notes \| Maximum
Debt Instrument [Line Items]
Convertible debt, conversion rate				0.0431406
2028 Notes \| Convertible Debt
Debt Instrument [Line Items]
Proceeds from convertible debt			$ 693.3
Debt issuance costs	$ 11.0			$ 11.0
Debt instrument, term				7 years
Effective interest rate	0.22%			0.22%