Stock compensation and other employee benefit plans - Outstanding option awards (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares
Share-Based Payment Arrangement [Abstract]
Outstanding, beginning balance, Shares | shares	7,538,265
Granted, Shares | shares	3,000,000
Exercised, Shares | shares	(3,316,079)
Forfeited and expired, Shares | shares	(412,336)
Outstanding, ending balance, Shares | shares	6,809,850
Vested or expected to vest in the future, Shares | shares	4,704,127
Exercisable , Shares | shares	2,105,723
Outstanding beginning balance, Weighted average exercise price | $ / shares	$ 2.48
Granted, Weighted average exercise price | $ / shares	3.86
Exercised, Weighted average exercise price | $ / shares	0.27
Forfeitures and expired, Weighted average exercise price | $ / shares	0.48
Outstanding ending balance, Weighted average exercise price | $ / shares	4.29
Vested or expected to vest in the future, Weighted average exercise price | $ / shares	5.59
Exercisable , Weighted average exercise price | $ / shares	$ 1.38
Outstanding , Weighted average remaining contractual term (years)	7 years 8 months 8 days
Vested or expected to vest in the future, Weighted average remaining contractual term (in years)	8 years 3 months 18 days
Exercisable, Weighted average remaining contractual term ( in years)	6 years 3 months 29 days
Outstanding , Average intrinsic value | $	$ 4,099
Vested or expected to vest in the future, Aggregate intrinsic value | $	580
Exercisable , Average intrinsic value | $	3,519
Stock-based compensation cost not yet recognized | $	$ 10,551
Weighted-average remaining expense recognition period (in years)	3 years 1 month 2 days