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Lease Exit Liability - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2017	Jul. 06, 2017	May 10, 2016
Restructuring Cost and Reserve [Line Items]
Future sublease payments to be received		$ 0.3	$ 2.4
Reduction in research and development expense	$ 1.3
Raven Biotechnologies Inc
Restructuring Cost and Reserve [Line Items]
Future sublease payments to be received				$ 1.3

X

- Definition

Reduction in R&D expense recorded in period

+ References

No definition available.

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- Definition

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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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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