Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Name:	us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

Revenue - Additional Information (Details1) - License and Collaboration Agreement [Member] - Neurocrine Biosciences [Member]	Sep. 30, 2020	Dec. 31, 2019
Development Services Under the Initial Development Program For DTCs [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-03-01
Disaggregation Of Revenue [Line Items]
Revenue remaining performance obligation excepted period	21 months
Exclusive License to XEN901 and Exclusive License to DTCs [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-12-31
Disaggregation Of Revenue [Line Items]
Revenue remaining performance obligation excepted period		15 months