Long-Term Debt and Other Financings - Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Interest expense
Interest expense	$ 1,844	$ 1,919
Silicon Valley Bank Loans
Interest expense
Interest expense	1,365	1,207
Novartis Note
Interest expense
Interest expense	477	706
Other
Interest expense
Interest expense	$ 2	$ 6