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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax Disclosure [Line Items] |  |  |
Income tax benefits for the net operating losses | $ 0 | $ 0 |
Valuation allowance | $ 90,477,000 | 72,791,000 | $ 53,834,000
Description of tax benefit likely to be realized upon settlement | greater than 50% |  |
Unrecognized tax benefits | $ 0 |  |
Interest or penalties accrued | $ 0 | 0 |
Income tax examination description | In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations. Tax years from 2018 to the present are open to examination under the statute. |  |
Federal |  |  |
Income Tax Disclosure [Line Items] |  |  |
Net operating loss carryforwards | $ 284,300,000 | 227,000,000.0 |
Net operating loss carryforwards subject to expiration | 79,400,000 |  |
Net operating loss carryforwards not subject to expiration | 204,900,000 |  |
Federal | Research and Development. |  |  |
Income Tax Disclosure [Line Items] |  |  |
Tax credit carryforwards | $ 4,500,000 |  |
Federal | Minimum [Member] |  |  |
Income Tax Disclosure [Line Items] |  |  |
Net operating loss carryforwards expiration year | 2034 |  |
Federal | Maximum |  |  |
Income Tax Disclosure [Line Items] |  |  |
Net operating loss carryforwards expiration year | 2037 |  |
State |  |  |
Income Tax Disclosure [Line Items] |  |  |
Net operating loss carryforwards | $ 270,700,000 | $ 213,600,000 |
Net operating loss carryforwards expiration year | 2029 |  |
State | Research and Development. |  |  |
Income Tax Disclosure [Line Items] |  |  |
Tax credit carryforwards | $ 2,900,000 |  |

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