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Related party transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Naspers
Related Party Transaction [Line Items]
Ownership percentage			5.00%
Affiliated Entity \| Naspers Ltd. and Other Entity
Related Party Transaction [Line Items]
Revenue from related parties	$ 0.3	$ 0.3	$ 1.1	$ 0.9
Accounts receivable, related parties	0.1		0.1		$ 0.1
Affiliated Entity \| Certain Vendors
Related Party Transaction [Line Items]
General and administrative expenses, related party	0.2	0.1	0.7	0.3
Accounts payable, related parties	0.0		0.0		$ 0.1
Board of Directors \| Enterprise Subscription Offering
Related Party Transaction [Line Items]
Revenue from related parties	$ 0.2	$ 0.0	$ 0.4	$ 0.0