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Revenue Recognition (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Research and Development Arrangements [Line Items]
Development revenue recognized		$ 4,771	$ 454	$ 5,810	$ 2,270
Reimbursement revenue recognized		$ 4,600
Customer Concentration Risk | Revenue Recognized [Member]
Research and Development Arrangements [Line Items]
Concentration risk percentage				100.00%
Customer Concentration Risk | Accounts Receivable [Member]
Research and Development Arrangements [Line Items]
Concentration risk percentage				100.00%
Subsequent Event
Research and Development Arrangements [Line Items]
Revenue received in cash	$ 4,600

X

- Definition

Aggregate revenue earned during the period from recognition of related party deferred revenue, non-product related activities and revenue earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

+ References

No definition available.

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Reimbursement revenue recognized.

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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.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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