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Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended
	Aug. 31, 2021	Apr. 30, 2021	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			$ 3,281,000	$ 3,680,000
Unrecognized Compensation Expense Period			2 years 4 months 24 days
Common stock, authorized			500,000,000		500,000,000
Number of Options, Granted			2,527,000	3,070,000
Outstanding Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			$ 692,000	$ 431,000
Vesting of RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			2,566,000	3,117,000
Unrecognized compensation expense			17,731,000
General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			$ 1,891,000	2,215,000
Zenith
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options, Granted			844,000
Zenith \| General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			$ 0	109,000
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			0
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense			$ 9,653,000
Unrecognized Compensation Expense Period			3 years 4 months 24 days
2018 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation arrangement vesting period			4 years
Amended 2018 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options, Granted		0
Amended 2018 Stock Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation arrangement vesting period		4 years
Share-based compensation arrangement, options granted		1,533,000
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period, weighted average grant date fair value		$ 21.55
Share-based payment arrangement, expense		$ 33,033,000
2021 Equity Incentive Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, authorized			15,500,000
2021 Equity Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation arrangement vesting period	4 years
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment arrangement, expense			$ 23,000	$ 23,000
Employee Stock Purchase Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based arrangement, quoted market price on purchase date			85.00%
Shares reserved for future issuance			2,000,000
Percentage of shares reserved for future issuance			1.00%
Minimum \| 2021 Equity Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation arrangement vesting period	1 year
Maximum \| 2018 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based arrangement term			10 years
Maximum \| 2021 Equity Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation arrangement vesting period	3 years
Maximum \| Employee Stock Purchase Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance						2,000,000