Fair Value Measurements (Details) - USD ($)	2 Months Ended	3 Months Ended		9 Months Ended
	Feb. 24, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Apr. 12, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
(Gain) loss on change in fair value of warrant liability		$ 0	$ 1,371,000	$ (14,000)	$ 1,312,000
2019 Refinancing Agreement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrants liability	$ 2,000,000	0		0		$ 2,000,000	$ 900,000
(Gain) loss on change in fair value of warrant liability	(100,000)		$ 1,400,000		$ 1,300,000
Wintrust Revolving Loan | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of debt	$ 39,000,000					$ 39,000,000
Wintrust Term Loan | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of debt		$ 26,500,000		$ 26,500,000