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Income Taxes - Additional Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax [Line Items] |  |  |
Deferred tax asset, valuation allowance eliminated | $ (3,344,000,000) |  | $ (3,344,000,000)
Net balance of deferred tax asset |  | $ 3,500,000 |
Deferred tax asset, valuation allowance |  | $ 379,000 | $ 388,000
Earliest Tax Year [Member] |  |  |
Income Tax [Line Items] |  |  |
Tax credit carryforwards expiration year |  | 2037 |
Tax credits expiration year |  | 2021 |
Latest Tax Year [Member] |  |  |
Income Tax [Line Items] |  |  |
Tax credit carryforwards expiration year |  | 2047 |
Tax credits expiration year |  | 2025 |
Research and Development Credit Carryforwards [Member] |  |  |
Income Tax [Line Items] |  |  |
Tax credit carryforward amount |  | $ 1,717,000 |
Research and Development Credit Carryforwards [Member] | Earliest Tax Year [Member] |  |  |
Income Tax [Line Items] |  |  |
Tax credit carryforwards expiration year |  | 2021 |
Research and Development Credit Carryforwards [Member] | Latest Tax Year [Member] |  |  |
Income Tax [Line Items] |  |  |
Tax credit carryforwards expiration year |  | 2039 |
Federal [Member] |  |  |
Income Tax [Line Items] |  |  |
Net operating loss carryforwards |  | $ 4,254,000 |
Operating loss carryforwards expiration year |  | 2038 |
State [Member] |  |  |
Income Tax [Line Items] |  |  |
Net operating loss carryforwards |  | $ 5,815,000 |

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