Collaborations - Change in Accounts Receivable, Contract Asset and Liabilities (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2026 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts receivable and contract assets, Beginning balance	$ 0
Accounts receivable and contract assets, Additions	65,000
Accounts receivable and contract assets, Deductions	(65,000)
Accounts receivable and contract assets, Ending balance	0
Contract Liabilities, Beginning balance	34,365
Contract Liabilities, Additions	0
Contract Liabilities, Deductions	(34,365)
Contract Liabilities, Ending balance	0
Billed Receivables - Sanofi
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts receivable and contract assets, Beginning balance	0
Accounts receivable and contract assets, Additions	20,000
Accounts receivable and contract assets, Deductions	(20,000)
Accounts receivable and contract assets, Ending balance	0
Billed Receivables - Gilead
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts receivable and contract assets, Beginning balance	0
Accounts receivable and contract assets, Additions	45,000
Accounts receivable and contract assets, Deductions	(45,000)
Accounts receivable and contract assets, Ending balance	0
Deferred Revenue - Gilead
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contract Liabilities, Beginning balance	34,365
Contract Liabilities, Additions	0
Contract Liabilities, Deductions	(34,365)
Contract Liabilities, Ending balance	$ 0