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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The current portion of deferred revenue from related parties as of balance sheet date. Current deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

No definition available.

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- Definition

Potential agreement term, from the effective date of agreement.

+ References

No definition available.

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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.

+ References

No definition available.

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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.

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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.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
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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

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.

+ References

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- Definition

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.

+ References

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
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-Subparagraph (SAB TOPIC 13.A.4(a).Q1)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section A
-Subsection 1

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- Definition

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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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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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
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-Publisher FASB
-Name Accounting Standards Codification
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Collaboration Agreements (Sanofi) (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2015	Dec. 31, 2017	Dec. 31, 2016
Collaboration Agreement [Line Items]
Accounts Receivable, Net, Current	$ 1,339,794				$ 1,343,368
Revenue from Related Parties	210,367	$ 219,694
Research and development	507,435	470,112
Deferred Revenue From Related Party Current	112,161				$ 115,267
Antibody Collaboration
Collaboration Agreement [Line Items]
Net profit (loss) from commercialization of products under collaboration agreement	(108,402)	(99,422)
Reimbursement of Regeneron research and development expenses	155,245	193,602
Reimbursement Revenue	73,559	68,722
Contracts Revenue	11,286	7,517
Revenue from Related Parties	$ 131,688	170,419
Percentage of Trial Costs borne by collaborating party	80.00%
Percentage of Trial Costs borne by entity	20.00%
IO Discovery Agreement
Collaboration Agreement [Line Items]
Annual Funding Maximum of Research Activities Per Agreement	$ 200,000
IO Agreement
Collaboration Agreement [Line Items]
Deferred Revenue, Additions			$ 640,000
Immuno-oncology Agreement
Collaboration Agreement [Line Items]
Recognition of Deferred Revenue	20,000	20,000
Reimbursement of Regeneron research and development expenses	58,679	29,275
Revenue from Related Parties	78,679	49,275
Praluent, sarilumab, and dupilumab [Member] \| Antibody Collaboration
Collaboration Agreement [Line Items]
Research and development	$ 25,000	$ 21,700
Scenario, Forecast [Member] \| Antibody Collaboration
Collaboration Agreement [Line Items]
Annual funding maximum of research activities per amended agreement				$ 130,000
Subsequent Event [Member] \| Antibody Collaboration
Collaboration Agreement [Line Items]
License agreement term				3 years