The aggregate amount of milestone payment made by the entity.

No definition available.

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- Definition

The amount of upfront payment based on the agreement.

+ References

No definition available.

+ Details

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- Definition

The amount of potential milestone payments under contractual obligation.

+ References

No definition available.

+ Details

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- Definition

Research Collaboration, Partner Royalty on Worldwide Net Sales, Term

+ References

No definition available.

+ Details

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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.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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Research Collaboration and License Agreement (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Research Collaboration and License Agreement
Research and development expense	$ 46,181,000	$ 25,705,000	$ 11,831,000
Research Collaboration and License Agreement
Research Collaboration and License Agreement
Term	10 years
Research Collaboration and License Agreement \| PTG-300
Research Collaboration and License Agreement
Upfront payment based on agreement	$ 250,000
Potential milestone payment on collaboration arrangement	250,000
Research and development expense	250,000	$ 250,000	$ 0
Research Collaboration and License Agreement \| Maximum \| PTG-300
Research Collaboration and License Agreement
Aggregate milestone payment	$ 128,500,000