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Stock-based compensation - Narrative (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation	$ 51,836	$ 12,716
Capitalized stock-based compensation expense related to internally developed software	$ 9,400	$ 2,700
Employee Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expiration period of stock options granted (in years)			10 years
Employee Stock Option \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period (in months)	12 months
Employee Stock Option \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period (in months)	48 months
Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation cost related to outstanding	$ 9,600
Weighted-average period of recognition (in years)	2 years 6 months
Restricted Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation cost related to outstanding	$ 424,900
Weighted-average period of recognition (in years)	3 years 4 months 24 days
Awards Associated With Business Combinations
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation cost related to outstanding	$ 31,400
Weighted-average period of recognition (in years)	1 year 8 months 12 days
Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized stock-based compensation cost related to outstanding	$ 1,900
Weighted-average period of recognition (in years)	4 months 24 days
Shares withheld for tax withholding requirements	1.0