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Amount of cost to be recognized for option under share-based payment arrangement.

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Stock-based Compensation - Compensation expense by award type (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock-based Compensation
Stock based compensation expense	$ 32,553	$ 19,831	$ 20,804
Research and development
Stock-based Compensation
Stock based compensation expense	8,449	5,814	7,687
Selling, general and administrative
Stock-based Compensation
Stock based compensation expense	24,104	14,017	13,117
2017 Equity Incentive Plan \| Employee
Stock-based Compensation
Unrecognized compensation expense related to non-vested portion of awards	$ 16,880
Weighted average period for recognition of unrecognized compensation expense	2 years 7 months 17 days
2017 Equity Incentive Plan \| Employees, directors and nonemployees
Stock-based Compensation
Unrecognized compensation expense related to non-vested portion of awards	$ 27,322
Weighted average period for recognition of unrecognized compensation expense	2 years 25 days
Stock options.
Stock-based Compensation
Stock based compensation expense	$ 17,671	15,477	17,988
Employees stock purchase plan
Stock-based Compensation
Stock based compensation expense	581	408	310
Restricted stock units
Stock-based Compensation
Stock based compensation expense	5,998	2,918	1,924
Performance stock units
Stock-based Compensation
Stock based compensation expense	$ 8,303	$ 1,028	$ 582