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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Summary of Significant Accounting Policies - Summary of Collaborators that Represent More Than 10% of Total Revenue Earned (Details) - Sales revenue, net - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Incyte Corporation (Incyte)
Concentration Risk [Line Items]
Percentage of all significant revenue earned	68.00%	96.00%	0.00%
Janssen Biotech, Inc. (Janssen)
Concentration Risk [Line Items]
Percentage of all significant revenue earned			85.00%
Provention Bio, Inc. (Provention)
Concentration Risk [Line Items]
Percentage of all significant revenue earned	10.00%	0.00%	0.00%