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Related Party Transactions - Additional Information (Detail) - Third Rock Venture [Member] - Consulting And Management Services [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Related Party Expense	$ 0	$ 200
Due To Related Parties	$ 0	$ 80

X

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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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.

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