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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Debt - Convertible senior notes (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) d $ / shares	Mar. 31, 2023 USD ($)	Mar. 31, 2021 USD ($)
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	$ 0.5	$ 0.6
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	$ 0.4	$ 0.4
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%