License and Collaboration Agreements - Summary of Accounts Recerivable, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current accounts receivable:
Billed to customers	$ 101	$ 265
Unbilled Zolgensma royalties	15,312	24,128
Due from Abeona, net of present value discount	$ 4,702	$ 4,587
Other Receivable, after Allowance for Credit Loss, Current, Related Party, Type [Extensible Enumeration]	Related Party [Member]	Related Party [Member]
Other unbilled	$ 415	$ 397
Allowance for credit losses	(4,702)	(4,587)
Current accounts receivable, net	15,828	24,790
Non-current accounts receivable:
Other unbilled	523	701
Non-current accounts receivable, net	523	701
Total accounts receivable, net	$ 16,351	$ 25,491

Allowance for credit losses, current.

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Other unbilled receivables current.

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Amount, after allowance for credit loss, of accounts and financing receivable. Includes, but is not limited to, notes and loan receivable.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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