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Fair Value of Financial Assets and Liabilities - Schedule of Assets and Liabilities Measured at Fair Value (Detail) - USD ($) | Sep. 30, 2021 | Dec. 31, 2020
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Fair Value, Measurements, Recurring |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Cash equivalents | $ 62,604,000 | $ 44,834,000
Fair value of derivative liability | 491,000 | 455,000
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Cash equivalents | 34,816,000 | 16,816,000
Fair value of derivative liability | 0 | 0
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Cash equivalents | 27,788,000 | 28,018,000
Fair value of derivative liability | 0 | 0
Fair Value, Measurements, Recurring | Level 3 |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Cash equivalents | 0 | 0
Fair value of derivative liability | 491,000 | $ 455,000
Measurement Input, Discount Rate |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |
Fair value of derivative liability | $ 0.14 |

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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