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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Tax Credit Carryforward [Line Items] |  |  |
Federal Income tax rate | 21.00% | 21.00% |
Net valuation allowance Increased (decreased) | $ 6,400,000 | $ 6,400,000 | $ (5,100,000)
Research and development tax credit carryforwards for federal and state | $ 1,356,000 | 705,000 |
Period for which cumulative change in ownership annual use net operating loss and research and development credit carryforwards | 3 years |  |
Accrued interest and penalties associated with uncertain tax positions | $ 0 | 0 |
Interest or penalties recorded during the year | $ 0 | 0 |
Minimum [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Percentage of cumulative change in ownership | 50.00% |  |
Domestic Tax Authority [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Federal net operating loss carryforwards | $ 46,900,000 | 14,400,000 |
Net operating loss carryforward expiration period | 2035 |  |
Federal net operating loss carryforwards, not to expiration | $ 46,100,000 |  |
Research and development tax credit carryforwards for federal and state | $ 1,900,000 | 1,000,000.0 |
Research and development tax credit carryforwards expiration period | 2036 |  |
State and Local Jurisdiction [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
State net operating loss carryforwards | $ 15,000,000.0 | 6,200,000 |
Research and development tax credit carryforwards for federal and state | $ 1,100,000 | $ 600,000 |
Research and development tax credit carryforwards expiration period | 2030 |  |
Research and development tax credit carryforwards expiration description | As of December 31, 2021 and 2020, the Company has state research and development credit carryforwards or approximately $1.1 million and $0.6 million, respectively, which will begin expiring in 2030 if not utilized |  |
Israeli Tax Authority [Member] | Foreign Country [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Income tax rate |  | 23.00% |
Foreign operating losses carryforwards | $ 7,900,000 | $ 7,900,000 |
California [Member] | State and Local Jurisdiction [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Net operating loss carryforward expiration period | 2035 |  |

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