ELAD Sales Agreement - Additional Information (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended		9 Months Ended
	May 28, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 04, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other income, net			$ 612	$ 904	$ 1,875	$ 1,512
ELAD-Related Assets | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration transferred		$ 2,500
Amount released from escrow	$ 1,100
Fair value of promissory note	920						$ 920
Other income, net				$ 405
ELAD-Related Assets | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Notes Receivable
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Face amount of receivable	$ 1,325						$ 1,300
Effective interest rate	10.00%
Vital Therapies, Inc. | ELAD-Related Assets | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Escrow deposit		1,100
Cash consideration		$ 50