Stock-based Compensation - Schedule of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Stock-based Compensation
Stock-based compensation expense	$ 2,316	$ 275
Future compensation cost for awards not vested	$ 11,200
Weighted-average period compensation cost of unvested awards to be expensed	3 years 3 months 18 days
Sesen Bio, Inc.
Stock-based Compensation
Stock-based compensation expense	$ 200
Research and development
Stock-based Compensation
Stock-based compensation expense	1,242	143
General and administrative
Stock-based Compensation
Stock-based compensation expense	$ 1,074	$ 132

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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