Fair Value Measurements - Financial assets at fair value on a recurring basis (Details) - Recurring basis - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financial assets:
Total financial assets	$ 934	$ 8,534
Cash equivalents-money market funds
Financial assets:
Total financial assets	934	8,534
Level 1
Financial assets:
Total financial assets	934	8,534
Level 1 \| Cash equivalents-money market funds
Financial assets:
Total financial assets	$ 934	$ 8,534

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

Name:	us-gaap_AssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant