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Stockholders' equity - Narrative (Details)			1 Months Ended	3 Months Ended				9 Months Ended
Stockholders' equity - Narrative (Details)	May 20, 2025 USD ($)	Jan. 01, 2025 shares	Feb. 28, 2025 quarter shares	Sep. 30, 2025 USD ($) quarter $ / shares shares	Mar. 31, 2025 quarter shares	Sep. 30, 2024 USD ($)	Mar. 31, 2024 shares	Sep. 30, 2025 USD ($) vote $ / shares shares	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) $ / shares shares	Oct. 29, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized (in shares)				50,000,000				50,000,000		50,000,000
Preferred stock, par value (in dollars per share) \| $ / shares				$ 0.00001				$ 0.00001		$ 0.00001
Number of votes per common stock \| vote								1
Share repurchase program shares authorized \| $				$ 50,000,000				$ 50,000,000		$ 150,000,000
Repurchases of common stock (in shares)				4,098,191
Repurchases of common stock \| $				$ 28,336,000		$ 51,423,000		$ 28,336,000	$ 142,535,000
Total shares of common stock reserved (in shares)				35,869,967				35,869,967		30,710,794
Stock-based compensation capitalized as a software \| $				$ 1,600,000		$ 2,300,000		$ 4,800,000	$ 6,800,000
RSUs Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)								9,750,922
Unrecognized compensation costs, excluding options \| $				128,200,000				$ 128,200,000
Unrecognized compensation costs, period for recognition (in years)								2 years 4 months 24 days
Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares right to receive (in shares)								1
Granted (in shares)								925,169
Unrecognized compensation costs, excluding options \| $				$ 4,800,000				$ 4,800,000
Unrecognized compensation costs, period for recognition (in years)								1 year 4 months 24 days
Performance-Based Awards \| Q3 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				553,125
Award vesting schedule \| quarter				6
Corporate performance metric attainment percentage				1				1
Performance-Based Awards \| Q1 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					372,044
Award vesting schedule \| quarter					8
Corporate performance metric attainment percentage				0.60				0.60
Performance-Based Awards \| Q1 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			218,565				553,568
Award vesting schedule \| quarter			12
Corporate performance metric attainment percentage			0.45
Performance-Based Awards \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			25.00%	33.33%
Performance-Based Awards \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage				66.67%
Performance-Based Awards \| Tranche Two \| Q1 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			75.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)								4 years
Contractual term (in years)								10 years
Stock options outstanding (in shares)				957,359				957,359		1,401,086
Incremental compensation cost \| $	$ 1,700,000
Contingently issuable shares under ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, excluding options \| $				$ 4,200,000				$ 4,200,000
Unrecognized compensation costs, period for recognition (in years)								1 year 7 months 6 days
Total shares of common stock reserved (in shares)		1,474,842									2,800,000
Minimum annual increase in shares reserved for issuance								1.00%
Percent of outstanding shares								300.00%
Shares issued (in shares)								430,926
Minimum \| RSUs Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)								2 years
Minimum \| Performance-Based Awards \| Q1 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					0.00%
Minimum \| Performance-Based Awards \| Q1 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage							0.00%
Maximum \| RSUs Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)								4 years
Maximum \| Performance-Based Awards \| Q1 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					150.00%
Maximum \| Performance-Based Awards \| Q1 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage							150.00%
2021 Stock incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)				13,800,000				13,800,000
Annual percentage increase								0.05
Number of shares reserved for future issuance increased (in shares)		7,374,214
Stock options outstanding (in shares)				907,359				907,359		1,351,086
Amended and Restated 2010 Equity Incentive Plan \| Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)				50,000				50,000
Exercisable, awards outstanding (in shares)				47,916				47,916