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Maximum potential success payments.

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Payment to collaborators.

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Potential amount of milestone payments and royalties payable.

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License and Collaboration Agreements - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended			3 Months Ended			9 Months Ended		12 Months Ended
	Aug. 31, 2026	Apr. 30, 2026	Mar. 31, 2019	Sep. 30, 2026	Jun. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2021	Dec. 31, 2025	Oct. 31, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Common stock, shares issued				299,521			299,521			266,732
Net proceeds from issuance of common stock							$ 89,622,000	$ 109,724,000
Issuance of common stock allocated to stock purchase option					$ 3,688,000
Additional Paid-in Capital
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Issuance of common stock allocated to stock purchase option					$ 3,688,000
Mayo Clinic Initial Shares \| Stock Purchase Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Stock price price per share		$ 3.33
Common stock, shares issued	7,500	7,500
Net proceeds from issuance of common stock		$ 25,000,000
Mayo Clinic Initial Shares \| Stock Purchase Agreement \| Common Stock and Additional Paid-in Capital
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Issuance of common stock allocated to stock purchase option							21,300,000
Mayo Clinic Election \| Stock Purchase Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Stock price price per share	$ 3.33
Net proceeds from issuance of common stock	$ 25,000,000
Mayo Clinic Election \| Stock Purchase Agreement \| Additional Paid-in Capital
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Issuance of common stock allocated to stock purchase option							3,700,000
Beam Therapeutics Inc. (Beam) \| Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment to collaborators									$ 50,000,000
Beam Therapeutics Inc. (Beam) \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Developmental and commercial milestone payments and royalties on licensed products payable											$ 65,000,000.0
Beam Therapeutics Inc. (Beam) \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Beneficial ownership percentage held by a member of board of directors											10.00%
Harvard College
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Share issue price			$ 4.00
Aggregated consideration paid			$ 12,000,000.0
Common stock shares issued			9,000,000.0
Payment to collaborators			$ 3,000,000.0
Maximum period expected to achieve for success payments			12 years
Harvard College \| Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Expense (gain) in connection with change in estimated fair value of success payment liability				$ 300,000		$ (300,000)	$ 400,000	$ (700,000)
Harvard College \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Cobalt success payment			$ 175,000,000.0