Amount of accrued offering costs included in accounts payable and accrued expenses.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

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Amount of contingent consideration recognized as part of consideration transferred in asset acquisition.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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PROLEUKIN ACQUISITION - Additional information (Details) $ in Thousands, £ in Millions			3 Months Ended
	May 18, 2023 USD ($)	May 18, 2023 GBP (£)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2024 GBP (£)
PROLEUKIN ACQUISITION
Finite-lived intangible assets				$ 17,500	£ 13.9
Accrued offering costs in accounts payable and accrued expenses			$ 0	552
PROLEUKIN
PROLEUKIN ACQUISITION
Total cost of acquisition	$ 222,672		222,700
Cash payment	207,200	£ 166.9	210,200
Direct transaction costs incurred			$ 12,500
Contingent cash payments, milestone payment	$ 52,600	£ 41.7
Deferred consideration term	12 years	12 years
Contingent consideration paid for acquisition				$ 52,600	£ 41.7
PROLEUKIN \| Developed technology
PROLEUKIN ACQUISITION
Expected useful life of intangible assets	15 years	15 years
Weighted average amortization period			14 years 9 months 18 days
PROLEUKIN \| Assembled workforce
PROLEUKIN ACQUISITION
Weighted average amortization period			14 years 9 months 18 days
PROLEUKIN \| Assembled workforce \| Selling, general and administrative
PROLEUKIN ACQUISITION
Expected useful life of intangible assets	3 years	3 years