Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Long-term debt
Less: Amounts due within one year	$ (2,041)
Total long-term debt	5,686	$ 34,502
Maturities of long-term debt
2021	2,041
2022	2,493
2023	4,084
Term loan
Long-term debt
Term loan payable	5,000	35,000
End of term fee	2,048	443
Unamortized debt issuance costs	(206)	(1,742)
Total long-term debt	6,842	33,701
Other long-term debt
Long-term debt
Total long-term debt	$ 885	$ 801