Gross proceeds from issuance of common stock.

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Option exercisable period for purchase additional shares.

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No definition available.

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Option to purchase additional shares of common stock.

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Percentage of commission on sale of common stock.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

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The cash inflow from the additional capital contribution to the entity.

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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.

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No definition available.

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Price of a single share of a number of saleable stocks of a company.

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Number of new stock issued during the period.

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Common Stock and Stock-Based Awards - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Jun. 29, 2022 USD ($) $ / shares shares	Aug. 12, 2020 USD ($) $ / shares shares	May 31, 2021 USD ($)	Nov. 30, 2019 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Jul. 01, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized					200,000,000	200,000,000
Common stock, par value \| $ / shares	$ 3.15				$ 0.001	$ 0.001
Common stock, shares issued	8,738,243
Net proceeds from sale of common stock \| $	$ 27,525				$ 96,721	$ 0	$ 243,748
Common stock, shares issued					125,222,273	91,889,418
Flagship Pioneering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net proceeds from sale of common stock \| $	$ 27,525
Underwriting Agreement [Member] \| Cowen and Company, LLC and Piper Sandler & Co. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net proceeds from sale of common stock \| $		$ 243,748
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued					31,746,030		12,075,000
Common Stock [Member] \| Underwriting Agreement [Member] \| Cowen and Company, LLC and Piper Sandler & Co. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued		10,500,000
Common stock, share price \| $ / shares		$ 21.50
Option exercisable period for purchase additional shares		30 days
Common Stock [Member] \| Maximum [Member] \| Underwriting Agreement [Member] \| Cowen and Company, LLC and Piper Sandler & Co. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option to purchase additional shares of common stock		1,575,000
Initial Public Offering ("IPO") [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized								200,000,000
Common stock, par value \| $ / shares	$ 3.15							$ 0.001
Common stock, shares issued	31,746,030
Additional net proceeds from the registered direct offering \| $	$ 96,721
At The Market Equity Offering Program [Member] \| 2019 Sales Agreement [Member] \| Cowen And Company, LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Gross proceeds from sale of common stock \| $				$ 25,000,000
At The Market Equity Offering Program [Member] \| 2019 and 2020 Sales Agreement [Member] \| Cowen And Company, LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued							5,788,000
Common stock, share price \| $ / shares							$ 4.40
Net proceeds from sale of common stock \| $							$ 24,773
Percentage of commission on sale of common stock							3
At The Market Equity Offering Program [Member] \| 2020 and 2021 Sales Agreement [Member] \| Cowen And Company, LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued						0
At The Market Equity Offering Program [Member] \| 2021 Sales Agreement [Member] \| Cowen And Company, LLC [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued					655,000
Common stock, share price \| $ / shares					$ 7.26
Net proceeds from sale of common stock \| $					$ 4,447
Gross proceeds from sale of common stock \| $			$ 150,000,000
Percentage of commission on sale of common stock					3
Concurrent Placement [Member] \| Securities Purchase Agreement [Member] \| Nestlé [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued		959,002
Common stock, share price \| $ / shares		$ 20.855
Net proceeds from sale of common stock \| $		$ 19,900