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Accrued Expenses - Summary of Accrued expenses and other current liabilities (Detail) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
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Accrued Expenses [Abstract] |  |
Accrued employee compensation and benefits | $ 3,751 | $ 6,150
Accrued external research and development expenses | 3,028 | 1,772
Accrued professional fees | 1,058 | 940
Deferred rent |  | 1,389
Other | 1,218 | 702
Total | $ 9,055 | $ 10,953

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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for external research and development expenses. + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6911-107765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6935-107765 + Details
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- Definition For a classified balance sheet, the cumulative difference as of the balance sheet date between the payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, within one year of the balance sheet date. + 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 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e39927-112707 + Details
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