Janssen Collaboration Agreement (Details) - Collaborative Arrangement, Product [Member] - USD ($)	3 Months Ended
Sep. 30, 2017	Jun. 30, 2017
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative arrangement, percentage of development costs incurred		20.00%
Janssen Biotech, Inc. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative arrangement, percentage of development costs incurred		80.00%
Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Nonrefundable upfront payment	$ 50,000,000
Revenue recognition, milestone method, revenue recognized	$ 615,000,000
Collaboration agreement, detail capital required for commercial launch, percent (up to)	30.00%
First Opt-in [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Future opt-in payment eligible to receive under collaboration arrangement	$ 125,000,000
Second Opt-in [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Future opt-in payment eligible to receive under collaboration arrangement	$ 200,000,000

Collaboration Agreement, Detail Required For Commercial Launch, Percent

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

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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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