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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
	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

X

- 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

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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

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+ References

No definition available.

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