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Stock-Based Compensation - Expense and ESPP (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock-Based Compensation
Unrecognized compensation expense	$ 18,068		$ 18,068
Remaining unamortized expense period			1 year 7 months 6 days
Stock options
Stock-Based Compensation
Share-based compensation costs recognized	4,483	$ 4,885	$ 12,790	$ 17,219
Stock options \| OnkosXcel Warrants
Stock-Based Compensation
Share-based compensation costs recognized	4,483	4,885		17,219
Stock options \| Research and development expense
Stock-Based Compensation
Share-based compensation costs recognized	1,105	951	3,310	5,155
Stock options \| Selling, general and administrative
Stock-Based Compensation
Share-based compensation costs recognized	$ 3,378	$ 3,934	$ 9,480	$ 12,064