Consolidated Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Research and Development Expense
Research and development expense related party	$ 0	$ 0	$ 1,885
General and Administrative Expense
General and administrative expense related party	0	0	15
Interest Expense
Interest expense, related party	$ 0	$ 147	$ 52