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Stock-based compensation - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jun. 06, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation		$ 53,600	$ 435,000	$ 105,435	$ 447,682
Capitalized stock-based compensation expense related to internally developed software	$ 62,700	$ 13,800	$ 65,600	$ 23,200	$ 68,300
Unvested Options outstanding (in shares)		8,300,000		8,300,000
Share-based payment arrangement, expense	$ 423,800
Shares withheld for tax withholding requirements	4,000,000.0
Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average period of recognition (in years)				2 years 4 months 24 days
Restricted Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average period of recognition (in years)				3 years 2 months 12 days
Share-based payment arrangement, expense				$ 423,800
Capitalized costs		$ 62,700		62,700
Unrecognized stock-based compensation cost related to outstanding		408,700		$ 408,700
Awards Associated With Business Combinations
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average period of recognition (in years)				1 year 6 months
Unrecognized stock-based compensation cost related to outstanding		25,800		$ 25,800
Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average period of recognition (in years)				2 months 12 days
Unrecognized stock-based compensation cost related to outstanding		$ 800		$ 800
Shares withheld for tax withholding requirements				4,500,000
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