Fair value of financial instruments and marketable securities - Convertible senior notes (Details) - Convertible debt - USD ($) $ in Millions |
Sep. 30, 2026 |
Jun. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2019 |
|---|---|---|---|---|
| 2031 Convertible Notes | ||||
| Long-term debt | ||||
| Principal | $ 550.0 | |||
| Interest rate ( as a percent ) | 0.00% | |||
| Additional amount available for purchase | $ 50.0 | |||
| 2031 Convertible Notes | Significant other observable inputs (Level 2) | ||||
| Long-term debt | ||||
| Fair value of convertible notes | $ 506.8 | |||
| 2026 Convertible Notes | ||||
| Long-term debt | ||||
| Principal | $ 287.5 | |||
| Interest rate ( as a percent ) | 1.50% | |||
| Additional amount available for purchase | $ 37.5 | |||
| 2026 Convertible Notes | Significant other observable inputs (Level 2) | ||||
| Long-term debt | ||||
| Fair value of convertible notes | $ 424.5 |
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- Definition Represents the additional amount available for purchase of debt instrument. No definition available.
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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