Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) Institution segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Oct. 31, 2020 USD ($)
Accounting Policies
Number of operating segments | segment		1
Number of financial institutions | Institution		2
Short-term financing arrangement					$ 600
Other current liability		$ 435
Operating lease right-of-use assets		930	$ 1,054
Operating lease liability		$ 191	163
Practical Expedient, Financing Component		true
Prepaid expenses research and development		$ 2,500	2,800
Charges incurred		0	0	$ 0
Uncertain tax positions		$ 0	$ 0	$ 0
Minimum
Accounting Policies
Equipment depreciation period		3 years
Maximum
Accounting Policies
Equipment depreciation period		5 years
Employees
Accounting Policies
Stock options, vesting period		4 years
Board of Director
Accounting Policies
Stock options, vesting period		1 year
BioCryst
Accounting Policies
Fixed expense reimbursement	$ 6,000