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Debt - Convertible senior notes (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($)	Dec. 31, 2024 USD ($) d $ / shares	Dec. 31, 2023 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
Interest expense		$ 2.2	$ 2.2
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
Debt instrument, term		5 years
Effective interest rate		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
Interest expense		$ 1.6	$ 1.6
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
Debt instrument, term		7 years
Effective interest rate		0.22%