Collaborative Arrangements and Revenue Recognition - Summary of Revenues Disaggregated by Recognition at Point in Time and Over Time (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Point in Time
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 966
Over Time
Disaggregation of Revenue [Line Items]
Revenues	0	475
Healios \| Point in Time \| Product supply revenue
Disaggregation of Revenue [Line Items]
Revenues	0	966
Healios \| Point in Time \| Service revenue
Disaggregation of Revenue [Line Items]
Revenues	0	0
Healios \| Over Time \| Product supply revenue
Disaggregation of Revenue [Line Items]
Revenues	0	0
Healios \| Over Time \| Service revenue
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 475

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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