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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |
Increase in valuation allowance | $ 124,000,000.0 | $ 19,900,000 | $ 34,400,000
Deferred tax asset for temporary difference | 78,700,000 |  |
Federal and state net operating loss carryforwards | 134,033,000 | 91,267,000 |
Foreign net operating loss carryforwards | $ 32,417,000 | $ 37,786,000 |
Percentage of ownership changes | 0.00% |  |
Unrecognized tax benefits | $ 48,600,000 |  |
Accrued interest, unrecognized tax benefits | 0 |  | $ 0
Unrecognized tax benefits that would affect effective tax rate | $ 500,000 |  |
Unrecognized tax benefits description | The Company does not anticipate a material change to its unrecognized tax benefits over the next twelve months that would affect the Company’s effective tax rate. |  |
Earliest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Foreign statute of limitation generally remains open in the year | 2011 |  |
Latest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Foreign statute of limitation generally remains open in the year | 2020 |  |
Foreign net operating loss [Member] |  |  |
Income Taxes [Line Items] |  |  |
Foreign net operating loss carryforwards | $ 172,900,000 |  |
Foreign net operating loss [Member] | Minimum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Operating loss carryforwards expiration year | 2021 |  |
Foreign net operating loss [Member] | Maximum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Operating loss carryforwards expiration year | 2030 |  |
Federal [Member] |  |  |
Income Taxes [Line Items] |  |  |
Federal and state net operating loss carryforwards | $ 606,800,000 |  |
Operating loss carryforwards expiration year | 2026 |  |
Other tax credit carryforwards | $ 66,900,000 |  |
Other tax credit carryforwards expiration year | 2021 |  |
State [Member] |  |  |
Income Taxes [Line Items] |  |  |
Federal and state net operating loss carryforwards | $ 133,600,000 |  |
Operating loss carryforwards expiration year | 2021 |  |
State [Member] | California [Member] |  |  |
Income Taxes [Line Items] |  |  |
Other tax credit carryforwards | $ 32,900,000 |  |

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