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Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	May 31, 2017	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Oct. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	6 months
Options outstanding (in shares)		12,839,612		10,098,929
Weighted-average exercise price of stock options outstanding (in dollars per share)		$ 15.50		$ 18.58
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense		$ 4,833	$ 5,274
2016 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized (in shares)	800,000
Payroll deduction percentage	10.00%
Purchase price of common stock percent of the fair market value	85.00%
Common stock purchased (in shares)		0
2003 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)		61,572
Stock Incentive Plan 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized (in shares)		15,816,949
Options outstanding (in shares)		12,778,040
Potential annual increase in shares reserved for future issuance (in shares)					1,960,168
Potential annual increase in shares reserved for future issuance as percentage of outstanding share		4.00%
Research and Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense		$ 2,461	2,392
General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense		$ 2,372	$ 2,882

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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