Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 2,237	$ 1,421
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	1,594	1,135
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 643	$ 286