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Provision for Income Taxes - Additional Information (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Taxes [Line Items] |  |  |  |
Valuation allowance increased value | $ 33,800,000 | $ 19,700,000 | $ 12,200,000 |
Net operating loss carryforwards | 253,300,000 |  |  |
Interest or penalties accrued | 0 | 0 | 0 |
Liability related to uncertain tax positions | 0 |  |  |
Reserve for unrecognized tax benefits | 3,153,000 | $ 2,165,000 | $ 1,084,000 | $ 622,000
Federal |  |  |  |
Income Taxes [Line Items] |  |  |  |
Net operating loss carryforwards | $ 47,400,000 |  |  |
Net operating loss carryforwards, expiration year | 2035 |  |  |
Net operating loss carryforwards amount with no expiration date | $ 205,900,000 |  |  |
Federal | Earliest Tax Year | U.S. |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2015 |  |  |
Federal | Latest Tax Year | U.S. |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2019 |  |  |
Federal | Research |  |  |  |
Income Taxes [Line Items] |  |  |  |
Research tax credits | $ 9,900,000 |  |  |
Research tax credits, expiration year | 2035 |  |  |
State |  |  |  |
Income Taxes [Line Items] |  |  |  |
Net operating loss carryforwards | $ 15,900,000 |  |  |
Net operating loss carryforwards, expiration year | 2035 |  |  |
State | Earliest Tax Year | California |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2015 |  |  |
State | Latest Tax Year | California |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2019 |  |  |
State | Research |  |  |  |
Income Taxes [Line Items] |  |  |  |
Research tax credits | $ 5,100,000 |  |  |
Foreign Tax Authority | Earliest Tax Year | Australian Taxation Office |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2017 |  |  |
Foreign Tax Authority | Latest Tax Year | Australian Taxation Office |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year | 2019 |  |  |

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