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Fair Value of Financial Instruments - Schedule of Calculation of Estimated Fair Value of Success Payment Liabilities (Details) - Success Payment Liabilities | 6 Months Ended | 12 Months Ended
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Jun. 30, 2021 | Dec. 31, 2020
Fair Value of Common Stock | Harvard |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability measurement input | 128.71 | 81.64
Fair Value of Common Stock | Broad Institute |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability measurement input | 128.71 | 81.64
Expected Volatility | Harvard |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability measurement input | 77 | 74
Expected Volatility | Broad Institute |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability measurement input | 76 | 74
Expected Term (years) | Minimum | Harvard |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability, term | 1 month 9 days | 4 months 6 days
Expected Term (years) | Minimum | Broad Institute |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability, term | 1 month 9 days | 4 months 6 days
Expected Term (years) | Maximum | Harvard |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability, term | 8 years | 8 years 5 months 26 days
Expected Term (years) | Maximum | Broad Institute |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Success payment liability, term | 8 years 10 months 9 days | 9 years 4 months 9 days

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- Definition Value of input used to measure derivative liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + 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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