Fair value measurements - Level 3 Significant Unobservable Inputs (Details) $ in Millions	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability value	$ 8.0	$ 38.4	$ 59.3	$ 30.4
Fair Value, Inputs, Level 3 | Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability value	$ 8.0
Fair Value, Inputs, Level 3 | Fair Value, Recurring | Discount rate | Discounted cash flow | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Business combination, contingent consideration, liability, measurement input	0.099
Fair Value, Inputs, Level 3 | Fair Value, Recurring | Probability of payment | Discounted cash flow | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Business combination, contingent consideration, liability, measurement input	0.250
Fair Value, Inputs, Level 3 | Fair Value, Recurring | Probability of payment | Discounted cash flow | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Business combination, contingent consideration, liability, measurement input	0.500