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Collaboration profit (loss) sharing

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Contract Option Exercise Fee

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Equity Method Investments, Expected Profit Share

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Equity method investment basis difference amortization period

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Estimated additional payments upon achievement of development and commercial milestones.

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No definition available.

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Payables To Divestiture Of Interest In Joint Venture

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Total upfront and milestone payments made to collaborative partner.

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No definition available.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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This element represents the undistributed income (or loss) of equity method investments, net of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations; such investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting.

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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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Collaborative and Other Relationships - Equity Method Investments (Details) ₩ in Millions, $ in Millions	1 Months Ended		3 Months Ended					6 Months Ended
	Apr. 30, 2022 USD ($)	Dec. 31, 2019	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 KRW (₩)	Mar. 31, 2022 KRW (₩)	Jan. 31, 2022 USD ($)	Dec. 31, 2021 KRW (₩)	Jan. 31, 2020 USD ($)	Nov. 07, 2018 USD ($)
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments								$ 2.6	$ 16.1
Collaboration profit (loss) sharing			$ 29.4			$ (15.2)		(87.9)	53.3
ADUHELM
Schedule of Equity Method Investments [Line Items]
Research and development expense								$ 275.0
Samsung Bioepis
Schedule of Equity Method Investments [Line Items]
Percentage of stake in entity maximum			49.90%					49.90%		49.90%
Amortization of basis differences															$ 675.0
Loss recorded on Samsung Bioepis joint venture			$ 5.9			34.3		$ 2.6	16.1
Income (loss) from equity method investments			13.0			41.6		17.0	30.6
Investment in Samsung Bioepis				$ 599.9						₩ 0.0			₩ 713,300.0
Collaboration profit (loss) sharing			58.3			69.9		122.7	138.4
Eisai
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments			28.9			40.1		210.6	$ 40.1
Due to Related Parties			56.0	46.5				$ 56.0
Eisai \| ADUHELM
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments			160.0	59.0	$ 45.0	$ 45.0
Samsung Bioepis
Schedule of Equity Method Investments [Line Items]
Proceeds from divestiture of interest in joint venture	$ 1,000.0
Investment in Samsung Bioepis \| ₩											₩ 581.6
Payables to divestiture of interest in joint venture												$ 1,300.0
Equity Method Investments, Expected Profit Share		45.00%						50.00%
Upfront and milestone payments made to collaborative partner							$ 100.0
Research and development expense							$ 63.0
Prepaid research and development expenses														$ 37.0
Accrued milestone payments			15.0
Estimated additional payments upon achievement of development and commercial milestones								$ 180.0
Contract Option Exercise Fee								60.0
Due to Related Parties			$ 121.1	$ 148.7				$ 121.1
Samsung Bioepis \| Payment Due At First Anniversary
Schedule of Equity Method Investments [Line Items]
Payables to divestiture of interest in joint venture												812.5
Samsung Bioepis \| Payment Due At Second Anniversary
Schedule of Equity Method Investments [Line Items]
Payables to divestiture of interest in joint venture												$ 437.5
Inventory \| Samsung Bioepis
Schedule of Equity Method Investments [Line Items]
Equity method investment basis difference amortization period								1 year 6 months
Developed technology \| Samsung Bioepis
Schedule of Equity Method Investments [Line Items]
Equity method investment basis difference amortization period								15 years