Period of time over which the up-front payment received was recognized as revenue.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response))
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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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

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

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- References

No definition available.

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- Definition

The amount of consideration recognized during the period for the milestone or milestones.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 28
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=68058744&loc=SL6892177-166501

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- References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Summary of Significant Accounting Policies (Details) - USD ($)	1 Months Ended		3 Months Ended		6 Months Ended		18 Months Ended
	Jun. 30, 2015	May 31, 2014	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2013	Dec. 31, 2016
Share-based Compensation
Expected term					6 years 3 months	6 years 3 months
Level 1
Fair Value Measurements
Carrying value of cash held in money market fund			$ 117,100,000		$ 117,100,000			$ 38,000,000
Level 2
Fair Value Measurements
Assets measured at fair value levels 2 or 3			0		0			0
Liabilities measured at fair value levels 2 or 3			0		0			0
Level 3
Fair Value Measurements
Assets measured at fair value levels 2 or 3			0		0			0
Liabilities measured at fair value levels 2 or 3			0		$ 0			$ 0
Maximum
Share-based Compensation
Expiration period					10 years
Pfizer \| License Agreement
Revenue Recognition
Milestone revenue			$ 0	$ 0	$ 0	$ 0
Pfizer \| License Agreement \| Up-Front Payment Arrangement
Revenue Recognition
Upfront payment revenue recognized							$ 22,500,000
Recognition period of up-front payment							1 year 6 months
Achievement Of Specified Development Milestone \| Pfizer \| License Agreement
Revenue Recognition
Milestone revenue	$ 20,000,000	$ 15,000,000