Subsequent Events - Neurimmune (Details) - Subsequent Event - Neurimmune $ in Millions	1 Months Ended
Oct. 31, 2017 USD ($)
Noncontrolling Interest [Line Items]
Payments to Neurimmune	$ 150.0
Reduction in royalty rate payable on commercial sales	15.00%
Additional reduction in royalty rate payable on commercial sales	5.00%
Additional potential payment to Neurimmune	$ 50.0

Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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