Stock-based compensation - Schedule of option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Price
Options expired (in dollars per share)	$ 17.12	$ 19.74
Performance stock units
Shares
Options expired (in shares)	(91,946)	(44,205)
2018 Stock Plan
Shares
Options outstanding, balance beginning (in shares)	1,486,428	1,598,811	1,916,101
Options exercised (in shares)	(197,703)	(112,383)	(286,842)
Options forfeited (in shares)			(30,448)
Options expired (in shares)	(2,795)
Options outstanding, balance ending (in shares)	1,285,930	1,486,428	1,598,811
Options vested and exercisable (in shares)	1,285,930
Price
Options outstanding, beginning balance (in dollars per share)	$ 3.54	$ 3.54	$ 3.54
Options exercised (in dollars per share)	3.54	3.54	3.54
Options forfeited (in dollars per share)			3.54
Options expired (in dollars per share)	3.54
Option outstanding, ending balance (in dollars per share)	3.54	$ 3.54	$ 3.54
Options vested and exercisable (in dollars per share)	$ 3.54
Additional Disclosures
Options outstanding, aggregate intrinsic value	$ 24,047	$ 14,552	$ 12,279	$ 65,971
Options vested and exercisable, aggregate intrinsic value	$ 24,047
Options outstanding, weighted average contractual term (in years)	4 years 21 days
Options vested and exercisable, weighted average contractual term (in years)	4 years 21 days
2020 Equity Incentive Plan
Shares
Options outstanding, balance beginning (in shares)	3,165,715	3,003,611	2,224,687
Options granted (in shares)	25,000	689,500	1,228,700
Options exercised (in shares)	(186,021)	(153,302)	(67,593)
Options forfeited (in shares)	(164,357)	(329,889)	(382,183)
Options outstanding, balance ending (in shares)	2,748,391	3,165,715	3,003,611
Options vested and exercisable (in shares)	2,014,869
Price
Options outstanding, beginning balance (in dollars per share)	$ 12.79	$ 13.22	$ 12.86
Options granted (in dollars per share)	12.65	11.49	14.67
Options exercised (in dollars per share)	10.20	8.67	9.69
Options forfeited (in dollars per share)	13.94	14.99	16.40
Option outstanding, ending balance (in dollars per share)	12.75	$ 12.79	$ 13.22
Options vested and exercisable (in dollars per share)	$ 12.25
Additional Disclosures
Options outstanding, aggregate intrinsic value	$ 26,881	$ 7,197	$ 3,883	$ 55,856
Options vested and exercisable, aggregate intrinsic value	$ 20,746
Options outstanding, weighted average contractual term (in years)	6 years 7 months 2 days
Options vested and exercisable, weighted average contractual term (in years)	6 years 1 month 28 days