Consolidated Statements of Cash Flows (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2019
Series B-1 redeemable convertible preferred shares
preferred shares, net of issuance costs	$ 50
Series B-2 redeemable convertible preferred shares
preferred shares, net of issuance costs		$ 230

The cash outflow for cost incurred directly with the issuance of an equity security.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

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