Financial instruments fair value - Narrative (Details) - Convertible Senior Notes Due 2026 - Convertible Debt - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 17, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Principal amount			$ 373.8
Debt issuances costs capitalized	$ 7.4	$ 9.2

Face (par) amount of debt instrument at time of issuance.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant