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Commitments and Contingencies - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			9 Months Ended
	Feb. 29, 2020	Nov. 30, 2019	Jan. 31, 2019	Sep. 30, 2021	Jan. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Feb. 28, 2019
Commitments And Contingencies Disclosure [Line Items]
Debt instrument interest rate								8.00%
Convertible notes issued								$ 0.2
Percentage of selling price per share that can convertible into equity securities sold								80.00%
Converted amount	$ 0.5
Series A Convertible Preferred Stock
Commitments And Contingencies Disclosure [Line Items]
Converted shares	301,685
Share price	$ 1.65816
May 2018 Note
Commitments And Contingencies Disclosure [Line Items]
Maturity description				on or after February 5, 2021, if not converted earlier
July 2018 Note
Commitments And Contingencies Disclosure [Line Items]
Maturity description				on or after February 5, 2021, if not converted earlier
February 2019 Note
Commitments And Contingencies Disclosure [Line Items]
Maturity description				on or after May 16, 2020, if not converted earlier
Unsecured Promissory Note \| January Note
Commitments And Contingencies Disclosure [Line Items]
Maturity description				on or before January 30, 2021
Percentage of final payment on advanced at maturity			3.00%
Debt instrument interest rate							10.00%	10.00%
Unsecured Promissory Note \| January Note \| Maximum
Commitments And Contingencies Disclosure [Line Items]
Notes issued			$ 0.5
Unsecured Promissory Note \| January Note \| Prime Plus
Commitments And Contingencies Disclosure [Line Items]
Debt instrument variable interest rate			4.50%
Unsecured Promissory Note \| November Note
Commitments And Contingencies Disclosure [Line Items]
Maturity description				on or before January 1, 2022
Percentage of final payment on advanced at maturity		3.00%
Debt instrument interest rate					9.25%	9.25%
Unsecured Promissory Note \| November Note \| Maximum
Commitments And Contingencies Disclosure [Line Items]
Notes issued		$ 0.5
Unsecured Promissory Note \| November Note \| Prime Plus
Commitments And Contingencies Disclosure [Line Items]
Debt instrument variable interest rate		4.50%
Unsecured Promissory Note \| February and March 2019 Draws \| January Note
Commitments And Contingencies Disclosure [Line Items]
Borrowings				$ 0.2
Unsecured Promissory Note \| Jan 2020 and Dec 2019 Draws \| November Note
Commitments And Contingencies Disclosure [Line Items]
Borrowings				0.4
Convertible Notes Issued in May and July 2018
Commitments And Contingencies Disclosure [Line Items]
Convertible notes issued				$ 0.3