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Stockholders’ deficit and stock-based compensation - Stock-based compensation and expense, narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Class of Stock [Line Items]
Options granted (in shares)	0
Compensation expense	$ 16.5	$ 45.5
ESPP
Class of Stock [Line Items]
Total unrecognized compensation cost	$ 14.7		$ 14.1
Weighted-average period of total unrecognized compensation cost, in years	1 year 3 months 18 days		3 years 7 months 6 days
Restricted Stock Units
Class of Stock [Line Items]
Total unrecognized compensation cost	$ 56.7
Weighted-average period of total unrecognized compensation cost, in years	2 years 8 months 4 days
Compensation expense	$ 0.0
Market-based RSUs
Class of Stock [Line Items]
Compensation expense	$ 8.0