Financial instruments fair value - Narrative (Details) - Convertible Senior Notes Due 2026 - Convertible Debt - USD ($) $ in Millions	Dec. 31, 2021	Sep. 17, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Debt, aggregate principal amount		$ 373.8
Debt issuances costs capitalized	$ 11.7

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

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