Amount of revenue recognized arising from contract liability from change in timeframe for performance obligation to be satisfied.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

Name:	us-gaap_ContractWithCustomerLiabilityChangeInTimeframePerformanceObligationSatisfiedRevenueRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Summary of Significant Accounting Policies - Subsequent Events (Details) - USD ($) $ in Thousands		3 Months Ended
	May 03, 2019	Mar. 31, 2019	Mar. 31, 2018
Subsequent Event [Line Items]
Revenue recognized that was previously deferred		$ 79	$ 7,834
Regulatory milestones \| Subsequent event \| Roche
Subsequent Event [Line Items]
Revenue recognized that was previously deferred	$ 5,000