Net Loss per Share - Antidilutive effect (Details) - shares	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	63,703,127	111,133,163
Finback BDA
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issuable upon exercise of warrant	532,038
Unvested warrants (in shares)	2,020,875
Options issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	21,567,577	21,600,629
Warrants to purchase common stock \| July 16, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	14,324,994	0
Warrants to purchase common stock \| January 13, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	2,552,913	2,552,913
Convertible preferred stock (as converted to common stock)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	0	80,833,007
Warrants to purchase preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	0	1,014,963
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	0	1,053,933
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	7,446,143	289,047
Unvested performance stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	914,000	0
Earn-out shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	15,000,000	0
Contingently issuable common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	1,897,500	0
Convertible notes (as converted to common stock)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the computation of diluted net loss per share (in shares)	0	3,788,671

Number of securities into which the class of warrant or right that may be exercisable.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The number of warrants or rights which entitle the entity to receive future services in exchange for the unvested, forfeitable warrants or rights.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section S99
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6784392&loc=d3e188667-122775

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