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Stock-based compensation - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended		12 Months Ended
	Jan. 31, 2021	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Service-based stock options that generally have a contractual life		8 years		8 years
Vesting period		2 years
Unrecognized compensation cost		$ 5.4
Weighted-average amortization period		1 year 9 months 18 days
Total incremental stock-based compensation expense		$ 1.0
Expected dividend yield		0.00%	0.00%
Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Service-based stock options that generally have a contractual life		10 years
Vesting period		4 years
2021 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of increase in number of shares reserved for issuance	4.00%
Common stock were authorized to be issued		4,076,746
Shares were available for future issuance	837,378	60,382