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Leases - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019
Operating Leased Assets [Line Items] |  |  |
Security deposits | $ 0.5 |  | $ 0.4
Cambridge, Massachusetts [Member] |  |  |
Operating Leased Assets [Line Items] |  |  |
Operating lease expiration period | 2024-09 |  |
Woburn Massachusetts [Member] |  |  |
Operating Leased Assets [Line Items] |  |  |
Operating lease expiration period | 2022-01 |  |
Seattle Washington [Member] |  |  |
Operating Leased Assets [Line Items] |  |  |
Lessee, Operating Lease, Term of Contract |  | 3 years |
Evansville [Member] |  |  |
Operating Leased Assets [Line Items] |  |  |
Operating lease expiration period | 2030-08 |  |
Lessee, Operating Lease, Term of Contract | 10 years |  |

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- Definition Date which lease is set to expire, in CCYY-MM format. + References No definition available. + Details
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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8,17) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Details
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- Details
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- Details
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- Details
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