Summary of Significant Accounting Policies - Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Detail) - shares
|
12 Months Ended |
Dec. 31, 2021 |
Dec. 31, 2020 |
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
105,116,667
|
19,646,572
|
| Unvested restricted common stock subject to repurchase |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
0
|
80,000
|
| Common stock to be purchased under the 2019 ESPP |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
508,656
|
204,664
|
| Options to purchase common stock |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
10,625,062
|
8,935,801
|
| Warrants to purchase common stock |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
67,767,107
|
10,426,107
|
| Series B-2 convertible preferred stock |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
8,333,334
|
0
|
| Convertible debt |
|
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |
|
|
| Potentially dilutive securities (in shares) |
17,882,508
|
0
|