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Charges related to program discontinuation

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Represents payments that may be made in the future contingent upon the achievement of regulatory and/or sales milestones as part of a collaborative arrangement.

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Milestone Payment to be Made to a Collaborative Partner

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Milestone Payments to be Made to a Collaborative Partner

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Research and Development Payments to be Made to a Collaborative Partner

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Royalty Rate, Percentage

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Upfront and milestone payments made to partner as part of collaborative arrangement.

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Upfront and Milestone Payments to be Made to Collaborative Partner

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- Definition

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 transaction cost incurred as part of consideration transferred in asset acquisition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Acquisitions, Research Collaborations and License Agreements (Details) - USD ($) $ in Millions	1 Months Ended				3 Months Ended		6 Months Ended
	Jul. 31, 2022	May 31, 2022	Apr. 30, 2021	Jan. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Business Acquisition [Line Items]
Research and development					$ 2,798.0	$ 4,321.0	$ 5,374.0	$ 6,732.0
Pandion Therapeutics
Business Acquisition [Line Items]
Research and development								1,700.0
Consideration transferred, asset acquisition			$ 1,900.0
Transaction cost, asset acquisition			147.0
Asset Acquisition, Other Assets and Liabilities Recognized, Net			$ 156.0
Orion Corporation \| Licensing Agreements \| Subsequent Event
Business Acquisition [Line Items]
Upfront and milestone payments	$ 290.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements
Business Acquisition [Line Items]
Upfront and milestone payments		$ 30.0
Milestone payments to be made to a collaborative partner		30.0
Milestone payment to be made to a collaborative partner		25.0
Research and development payments to be made to a collaborative partner		101.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Subsequent Event
Business Acquisition [Line Items]
Upfront and milestone payments	35.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Development Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement		90.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Development Milestones \| Subsequent Event
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement	82.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Regulatory Milestones \| Subsequent Event
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement	334.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Sales-Based Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement		780.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| Sales-Based Milestones \| Subsequent Event
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement	$ 485.0
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Licensing Agreements \| First Commercial Sale Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement		$ 290.0
Artiva Biotherapeutics, Inc. \| Licensing Agreements
Business Acquisition [Line Items]
Upfront and milestone payments				$ 30.0
Upfront and milestone payments to be made				$ 15.0
Artiva Biotherapeutics, Inc. \| Licensing Agreements \| Minimum
Business Acquisition [Line Items]
Royalty rate				7.00%
Artiva Biotherapeutics, Inc. \| Licensing Agreements \| Maximum
Business Acquisition [Line Items]
Royalty rate				14.00%
Artiva Biotherapeutics, Inc. \| Licensing Agreements \| Development Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement				$ 217.5
Artiva Biotherapeutics, Inc. \| Licensing Agreements \| Regulatory Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement				570.0
Artiva Biotherapeutics, Inc. \| Licensing Agreements \| Sales-Based Milestones
Business Acquisition [Line Items]
Contingent milestone payments collaborative arrangement				$ 1,050.0
COVID-19
Business Acquisition [Line Items]
Charges related to program discontinuation						$ 37.0		$ 207.0