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Represents the amount receivable as cost-sharing payments to be recorded as a reduction of research and development expense per research agreement.

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No definition available.

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Period from date of first commercial sale of product that the collaborative agreement expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Represents the milestone payments required, if certain research and development milestone events are achieved.

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No definition available.

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Represents the written notice period to terminate under the collaborative agreement.

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No definition available.

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Amount of deferred revenue allocated to a specific arrangement.

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No definition available.

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The number of clinical or regulatory milestones included in the transaction price of the agreement.

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No definition available.

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Period of time within which the Company agreed to provide the counterparty with electronic copies of certain know-how relating to development of product.

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No definition available.

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The number of novel, discovery-stage immuno-oncology programs the entity has the option to negotiate for licenses with counterparty.

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No definition available.

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Represents the period by which transaction price will be recognized as revenue.

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No definition available.

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Represents the period for recognizing performance obligation.

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Represents the potential payment that may be received upon achievement of specified milestones per agreement.

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No definition available.

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Represents the threshold period within which transaction price is recognized as revenue after entering into collaboration agreement.

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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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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets 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 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 revenue recognized that was previously reported as deferred or unearned revenue.

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Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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No definition available.

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Cash received from licensees for license fees during the current period.

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-Name Accounting Standards Codification
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The costs incurred 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 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, excluding in-process research and development acquired in a business combination consummated during the period. Excludes software research and development, which has a separate concept.

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License and Collaboration Arrangements (Details) $ in Thousands				1 Months Ended	3 Months Ended						12 Months Ended
	Sep. 30, 2016	Sep. 28, 2016 item	Apr. 05, 2016 USD ($)	Jul. 31, 2015 USD ($) item	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
License Agreements
License revenue					$ 15,700							$ 15,700
Research and development expense					66,122				$ 52,709
Zai Lab (Shanghai) Co., Ltd.
License Agreements
Proceeds from License Fees Received						$ 15,000
Jiangsu Hengrui Medicine Co., Ltd.
License Agreements
Upfront payment received				$ 1,000
Proceeds from License Fees Received				$ 1,000
Number of novel, discovery-stage immuno-oncology programs for which the Company has option to negotiate licenses \| item				2
License revenue				$ 1,000
Additional milestone payment				$ 1,000
Up-front payment arrangement
License Agreements
Deferred Revenue					376	$ 399			77		$ 376	399	$ 92
Deferred Revenue, Revenue Recognized					23				15
Up-front payment arrangement \| Janssen
License Agreements
Upfront payment received			$ 35,000
Research Agreement \| Merck
License Agreements
Research and development expense					2,100				800
Cost-sharing receivable					1,000				$ 400
Research Agreement \| Other current assets \| Merck
License Agreements
Cost-sharing receivable					1,100
Collaborative Arrangement
License Agreements
License revenue							$ 200
Transaction price							$ 14,800
Milestone payments required, if certain research and development milestone events are achieved					2,700						2,700
Collaborative Arrangement \| Janssen
License Agreements
Upfront payment received								$ 35,000
Threshold period within which transaction price is recognized as revenue after entering into collaboration agreement								30 days
Collaborative Arrangement \| Zai Lab (Shanghai) Co., Ltd.
License Agreements
Expiration period of collaborative arrangement	10 years
Number of clinical or regulatory milestones included in transaction price \| item		2
Collaborative Arrangement \| Achievement of clinical milestones \| Janssen
License Agreements
Potential milestone payments			43,000
Collaborative Arrangement \| Achievement of regulatory and sales milestones \| Janssen
License Agreements
Potential milestone payments			372,000
Collaborative Arrangement \| Achievement of clinical, regulatory and sales milestones \| Janssen
License Agreements
Potential milestone payments			$ 0
Collaborative Arrangement \| Minimum \| Janssen
License Agreements
Termination period			90 days
Collaborative Arrangement \| Maximum \| Janssen
License Agreements
Period of time to provide electronic copies of know-how relating to development of product			30 days
Collaborative Arrangement \| License arrangement \| Janssen
License Agreements
Amount of deferred revenue allocated to arrangement								$ 34,500
Collaborative Arrangement \| Joint Committee performance obligation arrangement \| Janssen
License Agreements
License revenue											34,600
Period for recognizing performance obligation								5 years
Amount of deferred revenue allocated to arrangement								$ 500
Deferred Revenue					$ 400						$ 400
Period by which transaction price will be recognized as revenue					48 months
License Agreement
License Agreements
License revenue					$ 2,000							$ 2,000
Transaction price										$ 1,900
Milestone payments required, if certain research and development milestone events are achieved										$ 100