Goodwill and intangible assets - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill	$ 287.1	$ 315.0	$ 108.6
Amortization expense	10.1	3.0	0.0
Other
Goodwill [Line Items]
Goodwill	$ 10.3	$ 10.3	$ 10.3