Fair Value of Financial Instruments - Summary of Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Class Of Warrant Or Right [Line Items]
Number of warrants issued	331,503
Warrants outstanding	331,503	180,819
Fair value of warrants	$ 4,225	$ 1,914
Series C-1
Class Of Warrant Or Right [Line Items]
Number of warrants issued	27,397
Purchase Price Per Share	$ 10.95
Warrants outstanding	27,397	27,397
Fair value of warrants	$ 240	$ 225
Series D
Class Of Warrant Or Right [Line Items]
Number of warrants issued	54,793
Purchase Price Per Share	$ 17.80
Warrants outstanding	54,793	54,793
Fair value of warrants	$ 557	$ 500
Series E
Class Of Warrant Or Right [Line Items]
Number of warrants issued	49,315
Purchase Price Per Share	$ 20.08
Warrants outstanding	49,315	49,315
Fair value of warrants	$ 615	$ 575
Series E
Class Of Warrant Or Right [Line Items]
Number of warrants issued	49,314
Purchase Price Per Share	$ 20.08
Warrants outstanding	49,314	49,314
Fair value of warrants	$ 636	$ 614
Series E
Class Of Warrant Or Right [Line Items]
Number of warrants issued	150,684
Purchase Price Per Share	$ 20.08
Warrants outstanding	150,684
Fair value of warrants	$ 2,177

Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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