Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended
	Mar. 31, 2024	May 31, 2022	Sep. 30, 2021	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of options granted (in dollars per share)					$ 13.20		$ 12.60
Stock-based compensation, net of amounts capitalized				$ 2,620	$ 4,690	$ 8,893	$ 15,662
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, period for recognition (in years)						2 years 6 months 3 days
Unrecognized compensation costs				11,800		$ 11,800
RSUs | New Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)						4 years
Award cliff vesting period (in years)						1 year
RSUs | Existing Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)						3 years
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)		40,000
Total grant date fair value		$ 4,000
Stock-based compensation, net of amounts capitalized				200	$ 400	$ 600	$ 1,300
Unrecognized compensation cost, period for recognition (in years)						1 year 11 months 8 days
Unrecognized compensation costs				400		$ 400
PSUs | Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of equity instruments vested during the period		1,300
PSUs | Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of equity instruments vested during the period		1,400
PSUs | Tranche 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of equity instruments vested during the period		$ 1,400
PSUs | Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	30,000
Total grant date fair value	$ 100
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, period for recognition (in years)						2 years 3 months 7 days
Unrecognized compensation cost related to unvested share-based compensation arrangements granted				$ 4,000		$ 4,000
2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, period for increase in shares (in years)			10 years
Percent of outstanding shares			4.00%
2021 Equity Incentive Plan | Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, maximum number of shares available for issue on the exercise of incentive stock options (in shares)			100,000,000
2021 Employee Stock Purchase Plan | 2021 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, period for increase in shares (in years)			10 years
Percent of outstanding shares			1.00%
Stock-based compensation, number of additional shares allowable under the plan (in shares)			142,500
Stock-based compensation, purchase period (in months)			6 months
2021 Employee Stock Purchase Plan | Class A Common Stock | 2021 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, discount percentage from market price, beginning of period			85.00%