Aggregate amount of twelve month sales upon which sales milestone would be received.

No definition available.

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- Definition

The maximum amount of sales milestone payments the Company is eligible to receive when and if total annual sales achieve certain specified levels.

+ References

No definition available.

+ Details

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- Definition

The percentage of subsequent Shared Phase 3 Trial costs borne by the collaborating party upon receipt of the first positive Phase 3 trial results for a co-developed drug candidate.

+ References

No definition available.

+ Details

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- Definition

The percentage of subsequent Shared Phase 3 Trial costs borne by the Company upon receipt of the first positive Phase 3 trial results for a co-developed drug candidate.

+ References

No definition available.

+ Details

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- Definition

Period for Achieving Sales Target for Milestone Payment, Rolling Basis

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Collaboration Agreements - Sanofi, Antibody Narrative (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Research and development	$ 1,048.3		$ 529.3	$ 1,690.1	$ 1,027.9
Cost of Treasury stock shares received		$ 54.0	37.6
Sanofi Collaboration Agreement, Antibody
Disaggregation of Revenue [Line Items]
Percentage of Trial Costs borne by collaborating party				80.00%
Percentage of Trial Costs borne by entity				20.00%
Treasury stock, shares acquired				24,143
Cost of Treasury stock shares received				$ 10.0
Maximum amount of sales milestone payments if total sales achieve specific levels				250.0
Levels of twelve month sales at which sales milestone payments would be received				$ 1,000.0
Period for achieving sales target for milestone payment, rolling basis				12 months
Praluent, Kevzara, and Dupixent \| Sanofi Collaboration Agreement, Antibody
Disaggregation of Revenue [Line Items]
Research and development	$ 10.3		$ 9.9	$ 19.6	$ 23.8