Stockholders' Equity - Common Stock and Private Placements (Details) $ / shares in Units, $ in Millions						1 Months Ended
	Dec. 04, 2020 USD ($) $ / shares shares	Jan. 22, 2020 shares	Dec. 24, 2019 USD ($) $ / shares shares	Jun. 15, 2019 shares	May 07, 2019 USD ($) $ / shares shares	Nov. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2021 vote shares	Dec. 31, 2020 shares	May 03, 2019 closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued (shares)							145,971,184	67,432,712
Common stock voting rights per share | vote							1
Number of years for increase of authorized shares		10 years
Common shares reserved for future issuance (in shares)							130,872,000
Number of closings (up to) | closing									2
Private Placement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)					9,730,534
Number of securities called by warrants (in shares)					9,730,534
Sale of stock (usd per share) | $ / shares					$ 1.205
Consideration received on transaction | $					$ 16.7
Convertible preferred stock, shares issued upon conversion (in shares)					10
Warrant exercise period					5 years
Warrant exercise price (usd per share) | $ / shares					$ 1.08
Private Placement | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)					526,083
Private Placement | Class A-1 Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)					4,158,980
Sale of stock (usd per share) | $ / shares					$ 10.80
Nonvoting convertible preferred stock issued (in shares)					415,898
Private Placement | Class A-1 Convertible Preferred Stock | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)					526,083
Proceeds from issuance of preferred warrants | $					$ 0.6
Private Placement | Class A-1 Convertible Preferred Stock | Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock (usd per share) | $ / shares					$ 0.125
Milestone Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Consideration received on transaction | $			$ 24.6
Milestone Closing | Class A-2 Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)			3,288,390
Number of securities called by warrants (in shares)			32,883,900
Consideration received on transaction | $			$ 26.0
Convertible preferred stock, shares issued upon conversion (in shares)			10
Warrant exercise price (usd per share) | $ / shares			$ 0.666
Warrants, term			5 years
Milestone Closing | Class A-2 Convertible Preferred Stock | Certain Directors and Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)			121,581
Number of securities called by warrants (in shares)			1,215,810
Consideration received on transaction | $			$ 1.0
2020 Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)	24,341,607
Number of securities called by warrants (in shares)	18,256,204
Sale of stock (usd per share) | $ / shares	$ 0.7464
Consideration received on transaction | $	$ 19.4
Convertible preferred stock, shares issued upon conversion (in shares)	10
2020 Closing | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)	833,208
2020 Closing | Class A-3 Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)	2,047,276
Sale of stock (usd per share) | $ / shares	$ 6.22
Nonvoting convertible preferred stock issued (in shares)	272,970
Warrant exercise price (usd per share) | $ / shares	$ 0.7464
Warrants, term	5 years
2020 Closing | Class A-3 Convertible Preferred Stock | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by warrants (in shares)	624,906
Proceeds from issuance of preferred warrants | $	$ 0.6
2020 Closing | Class A-3 Convertible Preferred Stock | Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock (usd per share) | $ / shares	$ 0.125
2021 Closing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)						58,923,352
Sale of stock (usd per share) | $ / shares						$ 0.36
Consideration received on transaction | $						$ 34.6
Convertible preferred stock, shares issued upon conversion (in shares)						10
2021 Closing | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)						2,222,222
2021 Closing | Class A-4 Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of stock (usd per share) | $ / shares						$ 3.60
Nonvoting convertible preferred stock issued (in shares)						3,725,720
2021 Closing | Class A-4 Convertible Preferred Stock | Directors, Executive Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from issuance of preferred warrants | $						$ 0.8
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares available (in shares)		4,166,860
Yearly authorized increase		5.00%
Shares available for future grant (in shares)							1,964,112
Common shares reserved for future issuance (in shares)							9,061,885
Prior Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				0