Product revenue and reserves - Summary of Product Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue from External Customer [Line Items]
Product revenue, net	$ 10,612	$ 12,281	$ 45,274	$ 21,414
ZYNTEGLO
Revenue from External Customer [Line Items]
Product revenue, net	5,493	4,851	35,212	9,031
LYFGENIA
Revenue from External Customer [Line Items]
Product revenue, net	2,632	0	2,632	0
SKYSONA
Revenue from External Customer [Line Items]
Product revenue, net	$ 2,487	$ 7,430	$ 7,430	$ 12,383

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details