Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2020
Series B-1
Share price (in dollars per share)	$ 3.9760		$ 3.9760
Share price (in dollars per share)			$ 2.7826
Adjustments to stock issuance costs	$ 2,838	$ 2,713
Series B-2
Share price (in dollars per share)	$ 3.9760

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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