The maximum annual amount of funding for research activities through 2017 per the amended agreement.

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The maximum amount of cost reimbursement the Company will receive on a annual basis.

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- Definition

Our share of profits/losses related to commercialization of products by our collaborator based on sales outside the United States. Under the terms of our collaboration agreement, we share profits/losses with our collaborator on commercialization of products.

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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.

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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.

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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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No definition available.

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Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product.

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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

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The amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. For cash flows, this element primarily pertains to amortization of deferred credits on long-term arrangements. As a noncash item, it is deducted from net income when calculating cash provided by or used in operations using the indirect method.

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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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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Collaboration Agreements (Sanofi) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2017	Dec. 31, 2016
Collaboration Agreement [Line Items]
Revenue from Related Parties	$ 163,414		$ 195,110		$ 383,108	$ 368,466
Research and development	559,930		390,330		1,030,042	733,443
ZALTRAP Agreement
Collaboration Agreement [Line Items]
Deferred revenue, revenue recognized				$ 14,900
Other Income	9,300		3,200		14,600	23,000
Reimbursement of Regeneron research and development expenses					0	686
Contracts Revenue					0	15,236
Revenue from Related Parties					0	15,922
Antibody Collaboration
Collaboration Agreement [Line Items]
Net profit (loss) from commercialization of products under collaboration agreement	(122,107)		(46,313)		(221,529)	(68,718)
Recognition of Deferred Revenue	3,054		2,560		6,019	5,121
Reimbursement of Regeneron research and development expenses	144,232		211,516		337,834	380,336
Contracts Revenue	85,885		27,347		159,159	35,805
Revenue from Related Parties	111,064		195,110		$ 281,483	352,544
Percentage of Trial Costs borne by collaborating party					80.00%
Percentage of Trial Costs borne by entity					20.00%
IO Agreement
Collaboration Agreement [Line Items]
Deferred Revenue, Additions		$ 640,000
Immuno-oncology Agreement
Collaboration Agreement [Line Items]
Recognition of Deferred Revenue	20,000		0		$ 40,000	0
Reimbursement of Regeneron research and development expenses	32,350		0		61,625	0
Revenue from Related Parties	52,350		0		101,625	0
Praluent, sarilumab, and dupilumab \| Antibody Collaboration
Collaboration Agreement [Line Items]
Research and development	$ 30,600		$ 22,500		$ 52,300	$ 47,500
Scenario, Forecast [Member] \| Antibody Collaboration
Collaboration Agreement [Line Items]
Annual funding maximum of research activities per amended agreement							$ 130,000	$ 130,000
Subsequent Event [Member] \| IO Agreement
Collaboration Agreement [Line Items]
Annual Funding Maximum of Research Activities Per Agreement								$ 150,000