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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Income Taxes [Line Items] |  |
Income tax benefits for the net operating losses | $ 0 | $ 0
Federal net operating loss carryforwards | 303,700,000 |
State net operating loss carryforwards | 302,600,000 |
Foreign net operating loss carryforwards | $ 4,400,000 |
Maximum increase in percentage ownership of stockholders or public groups | 50.00% |
Ownership change, increase in ownership percentage, term | 3 years |
Unrecognized tax benefits | $ 0 | 0
Accrued interest or penalties related to uncertain tax positions | $ 0 | $ 0
Federal corporate income tax rate | 21.00% | 21.00%
Domestic Country [Member] |  |
Income Taxes [Line Items] |  |
Federal net operating loss carryforwards, subject to expiration | $ 73,000,000 |
Federal net operating loss carryforwards, not subject to expiration | 230,700,000 |
Tax credit carryforward | $ 10,200,000 |
Tax credit carryforward expiration period | 2033 |
Domestic Country [Member] | Earliest Tax Year [Member] |  |
Income Taxes [Line Items] |  |
Net operating loss carryforwards expiration year | 2033 |
Domestic Country [Member] | Latest Tax Year [Member] |  |
Income Taxes [Line Items] |  |
Net operating loss carryforwards expiration year | 2037 |
State And Local Jurisdiction [Member] |  |
Income Taxes [Line Items] |  |
Tax credit carryforward | $ 2,200,000 |
Tax credit carryforward expiration period | 2028 |
State And Local Jurisdiction [Member] | Earliest Tax Year [Member] |  |
Income Taxes [Line Items] |  |
Net operating loss carryforwards expiration year | 2033 |
State And Local Jurisdiction [Member] | Latest Tax Year [Member] |  |
Income Taxes [Line Items] |  |
Net operating loss carryforwards expiration year | 2039 |

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