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Asset Acquisition, Cash and Equivalents

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Asset Acquisition, Consideration Transferred, Equity Interest Settled, Unvested

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Asset Acquisition, Consideration Transferred, Share-Based Equity Interest Settled

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Asset Acquisition, Deferred Tax Assets

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- Definition

Asset Acquisition, Investments

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- Definition

Asset Acquisition, Net Liabilities, Other

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- Definition

Asset Acquisition, Other Assets and Liabilities Recognized, Net

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- Definition

Asset Acquisition, Share Price

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- Definition

Collaborative Arrangement, Preferred Stock Investment In Counterparty

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- Definition

Collaborative Arrangement, Rights And Obligations, Maximum Aggregate Contingent Development-Related Payments

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Collaborative Arrangement, Rights And Obligations, Maximum Aggregate Regulatory Milestone Payments

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Collaborative Arrangement, Rights And Obligations, Maximum Aggregate Sales-Based Milestone Payments

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- Definition

Collaborative Arrangement, Rights And Obligations, Number of Antibody Drug Conjugates

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Collaborative Arrangement, Rights And Obligations, Terminated, Number Of Antibody Drug Conjugates

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Collaborative Arrangement, Stock Investment In Counterparty

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- Definition

Milestone Payment Made to Collaborative Partner

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- Definition

Option Payment Made to Collaborative Partner

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- Definition

Profit Share

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Profit Share Counterparty

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- Definition

Research And Development Arrangement, Contract To Perform For Others, Additional Funding By Others, Development Costs Subject to Funding

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Research And Development Arrangement, Contract To Perform For Others, Additional Funding By Others, Percentage Of Development Costs

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- Definition

Research and Development Payments Made To a Collaborative Partner

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- Definition

Research and Development Payments To Be Made to a Collaborative Partners

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- Definition

Royalty Rate, Percentage

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- Definition

Sales threshold

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- Definition

Upfront Payment 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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-Topic 805
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Amount of transaction cost incurred as part of consideration transferred in asset acquisition.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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- Definition

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 cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

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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 Licensing Agreements - Narrative (Details) $ / shares in Units, $ in Millions	1 Months Ended											6 Months Ended	12 Months Ended			20 Months Ended
	Feb. 29, 2024 USD ($)	Jun. 30, 2023 USD ($)	Feb. 28, 2023 USD ($) antibodyDrugConjugate	Jan. 31, 2023 USD ($)	Oct. 31, 2022 USD ($)	Aug. 31, 2022 USD ($)	Jul. 31, 2022 USD ($)	May 31, 2022 USD ($)	Nov. 30, 2021 USD ($)	Apr. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2024 USD ($) $ / shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 USD ($)	Oct. 31, 2023 USD ($) antibodyDrugConjugate
Business Acquisition [Line Items]
Research and development													$ 30,531	$ 13,548	$ 12,245
Harpoon Therapeutics, Inc. \| Subsequent Event \| Forecast
Business Acquisition [Line Items]
Asset acquisition, share price (in dollars per share) \| $ / shares												$ 23
Consideration transferred, asset acquisition												$ 680
Research and development												$ 650
Prometheus Biosciences, Inc.
Business Acquisition [Line Items]
Consideration transferred, asset acquisition		$ 11,000
Research and development													10,200
Consideration transferred, to settle share-based equity awards		1,200
Consideration transferred, to settle equity awards, unvested		700
Net assets acquired		877
Cash recorded for asset acquisition		368
Investments recorded for asset acquisition		296
Deferred tax assets recorded for asset acquisition		218
Other net liabilities recorded for asset acquisition		$ 5
Imago BioSciences, Inc.
Business Acquisition [Line Items]
Consideration transferred, asset acquisition				$ 1,350
Research and development													1,200
Net assets acquired				219
Transaction costs				60
Pandion Therapeutics
Business Acquisition [Line Items]
Consideration transferred, asset acquisition										$ 1,900
Research and development															$ 1,700
Consideration transferred, to settle share-based equity awards										147
Other net assets (liabilities)										$ 156
Elanco Animal Health Incorporated Aqua Business \| Subsequent Event
Business Acquisition [Line Items]
Cash paid for acquisition of business	$ 1,300
Acceleron Pharma Inc.
Business Acquisition [Line Items]
Cash paid for acquisition of business									$ 11,500
Transaction costs									$ 280
Daiichi Sankyo \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Research and development													5,500
Number of antibody drug conjugates obtained right and obligations \| antibodyDrugConjugate																	3
Orna Therapeutics \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Upfront payment made to collaborative partner						$ 150
Eligible future contingent development-related payments (up to)						440
Aggregate, regulatory milestones payments, maximum						675
Sales milestone payments						$ 2,400
Preferred stock investment in counterparty														$ 100
Orion Corporation \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Upfront payment made to collaborative partner							$ 290
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Number of antibody drug conjugates obtained right and obligations \| antibodyDrugConjugate			7
Upfront payment made to collaborative partner			$ 175				35
Number of antibody drug conjugates terminated with collaborative partner \| antibodyDrugConjugate																	2
Eligible future contingent development-related payments (up to)							82	$ 90									$ 725
Aggregate, regulatory milestones payments, maximum							334										1,950
Sales milestone payments							$ 485	780									$ 3,900
Stock investment in counterparty				$ 100
Option payment made to collaborative partner								30
Milestone payment to be made to a collaborative partner													$ 25
Research and development payments to be made to a collaborative partners																$ 111
Research and development payments made to a collaborative partner																$ 95
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| First Commercial Sale Milestones
Business Acquisition [Line Items]
Sales milestone payments								$ 290
Bristol Myers Squibb \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Business Acquisition [Line Items]
Royalty rate, percentage									22.00%
Gilead Sciences \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Oral and Injectable Formulations
Business Acquisition [Line Items]
Profit share by counterparty											60.00%
Profit share											40.00%
Gilead Sciences \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Oral Formulation
Business Acquisition [Line Items]
Profit share by counterparty											65.00%
Profit share											35.00%
Sales threshold											$ 2,000
Gilead Sciences \| Collaborative Arrangement, Transaction with Party to Collaborative Arrangement \| Injectable Formulation
Business Acquisition [Line Items]
Profit share by counterparty											65.00%
Profit share											35.00%
Sales threshold											$ 3,500
Royalty Pharma
Business Acquisition [Line Items]
Compensation earned on arragement					$ 50
Additional funding by others, percentage of development costs					50.00%
Additional funding by others, development costs subject to funding					$ 375