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Income Taxes - Additional Information (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |
Increased in valuation allowance | $ 25,000,000.0 | $ 23,700,000 |
Interest or penalties accrued | $ 0 | 0 |
California |  |  |
Income Taxes [Line Items] |  |  |
Research and experimental credits carryforwards, expiration | The California research and experimental tax credits carry forward indefinitely until utilized. |  |
Federal |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards subject to expiration | $ 78,400,000 | 80,400,000 |
Net operating loss carryforward not subject to expiration | $ 4,900,000 |  |
Net operating loss carryforwards latest expiration year | 2027 |  |
Net operating loss carryforwards |  |  | $ 73,500,000
Research and experimental credits carryforwards | $ 1,400,000 |  |
Research and experimental credits carryforwards, expiration | The federal research and experimental tax credits will begin to expire, if not utilized, in 2027. |  |
State |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss carryforwards latest expiration year | 2022 |  |
Net operating loss carryforwards | $ 50,100,000 | $ 51,100,000 |
Research and experimental credits carryforwards | $ 1,400,000 |  |

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32559-109319 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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