Equity Instruments (Tables)
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9 Months Ended | 
Sep. 30, 2022  | 
| Equity [Abstract] | 
 
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| Schedule of Shares of Common Stock Reserved for Issuance | 
Shares of common stock reserved for issuance on an “as if converted” basis were as follows:
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September 30, | 
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December 31, | 
 
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2022 | 
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2021 | 
 
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(share data) | 
 
| Common stock warrants | 
13,145,000  | 
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13,075,000  | 
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| Restricted stock units issued and outstanding | 
6,198,472  | 
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4,041,346  | 
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| Stock options issued and outstanding | 
17,731,063  | 
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21,191,226  | 
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| Shares available for future grant under 2021 Equity Incentive Plan | 
24,749,094  | 
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17,533,471  | 
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| Reserved for employee stock purchase plan | 
5,495,601  | 
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3,663,277  | 
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| Total shares of common stock reserved  | 
67,319,230 
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59,504,320 
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| Schedule of Warrants for Shares of Stock | 
Warrants for shares of common stock consisted of the following:
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September 30, 2022  | 
 
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Issue Date | 
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Expiration Date | 
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Number of Warrants | 
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Exercise Price per warrant | 
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Fair Value on Issue Date per warrant | 
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Fair Value on September 30, 2022  | 
 
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(In thousands) | 
 
| Private placement warrants  - Common Stock | 
12/02/2020 | 
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09/29/2026 | 
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4,450,000  | 
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$11.50 | 
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$2.00 | 
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3,605  | 
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| 2022 Private Warrant - Common Stock | 
07/25/2022 | 
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07/24/2034 | 
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70,000  | 
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$2.56 | 
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$2.43 | 
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245  | 
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| Public warrants - Common Stock | 
12/02/2020 | 
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09/29/2026 | 
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8,625,000  | 
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$11.50 | 
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$3.30 | 
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6,986  | 
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13,145,000  | 
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$ | 
10,836  | 
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December 31, 2021  | 
 
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Issue Date | 
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Expiration Date | 
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Number of Warrants | 
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Exercise Price per warrant | 
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Fair Value on Issue Date per warrant | 
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Fair Value on December 31, 2021  | 
 
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(In thousands) | 
 
| Private placement warrants  - Common Stock | 
12/02/2020 | 
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09/29/2026 | 
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4,450,000  | 
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$11.50 | 
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$2.00 | 
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7,387  | 
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| Public warrants - Common Stock | 
12/02/2020 | 
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09/29/2026 | 
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8,625,000  | 
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$11.50 | 
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$3.30 | 
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14,318  | 
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13,075,000  | 
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$ | 
21,705  | 
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| Warrant Liability Rollforward | 
The liability for warrants on common stock carried at fair value was as follows:
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Nine Months Ended September 30, | 
 
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2022 | 
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2021 | 
 
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(In thousands) | 
 
| Beginning Balance | 
$ | 
21,705  | 
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$ | 
—  | 
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| Issuance of warrants | 
170  | 
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21,051  | 
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| Gain (loss) on fair value of warrants | 
(11,039) | 
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(915) | 
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| Ending Balance | 
$ | 
10,836  | 
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$ | 
20,136  | 
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Three Months Ended September 30, | 
 
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2022 | 
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2021 | 
 
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(In thousands) | 
 
| Beginning Balance | 
$ | 
4,053  | 
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$ | 
—  | 
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| Issuance of warrants | 
170  | 
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21,051  | 
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| Gain (loss) on fair value of warrants | 
6,613  | 
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(915) | 
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| Ending Balance | 
$ | 
10,836  | 
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$ | 
20,136  | 
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The liability for warrants on redeemable convertible preferred stock (carried at fair value) was as follows: 
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Three Months Ended September 30, | 
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Nine Months Ended September 30, | 
 
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2021 | 
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2021 | 
 
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(In thousands) | 
 
| Beginning Balance | 
$ | 
1,922  | 
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$ | 
181  | 
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| Change in fair value (Other income (expense), net) | 
(1,023) | 
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718  | 
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| Exercise of warrants (Redeemable preferred convertible stock) | 
(899) | 
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(899) | 
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| Ending Balance | 
$ | 
—  | 
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$ | 
—  | 
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| Fair Value Assumptions | 
 The fair value assumptions used in the Monte Carlo simulation model for the recurring valuation of the private placement common stock warrant liability were as follows: 
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As of September 30, 2022  | 
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As of December 31, 2021  | 
 
| Current stock price | 
$ | 
3.94  | 
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$ | 
7.81  | 
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| Expected volatility | 
62.0  | 
% | 
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40.5  | 
% | 
 
| Risk-free interest rate | 
4.2  | 
% | 
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1.2  | 
% | 
 
| Dividend rate | 
—  | 
% | 
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—  | 
% | 
 
| Expected Term (years) | 
4.00 | 
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4.75 | 
 
  
The fair value assumptions used in the Black-Scholes simulation model for the recurring valuation of the 2022 Private Warrant liability were as follows: 
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As of September 30, 2022  | 
 
| Current stock price | 
$ | 
3.94  | 
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| Expected volatility | 
77.8  | 
% | 
 
| Risk-free interest rate | 
3.8  | 
% | 
 
| Dividend rate | 
—  | 
% | 
 
| Expected Term (years) | 
11.82 | 
 
  
Assumptions used in the fair value of the contingent earnout liabilities are described below.
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As of September 30, 2022  | 
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As of December 31, 2021  | 
 
| Current stock price | 
$3.94 | 
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$7.81 | 
 
| Expected volatility | 
78.6% | 
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52.5% | 
 
| Risk-free interest rate | 
4.2% | 
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1.2% | 
 
| Dividend yield | 
—% | 
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—% | 
 
| Expected Term (years) | 
4.00 | 
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4.75 | 
 
 
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| Schedule Of Contingent Earnout Liabilities | 
The rollforward for the contingent earnout liabilities was as follows:
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Nine Months Ended September 30, | 
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2022 | 
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| Beginning Balance | 
$ | 
111,487  | 
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| Gain on fair value of contingent earnout liabilities | 
(58,110) | 
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| Ending Balance | 
$ | 
53,377  | 
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