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Millendo Merger - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 25, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 68,413		$ 68,413			$ 18,820
Operating Lease, Right-of-Use Asset	3,673		3,673			$ 1,877
Operating Lease, Liability	4,158		4,158
Share-based compensation expense	411	$ 227	531	$ 230
General and Administrative Expense [Member]
Business Acquisition [Line Items]
Share-based compensation expense	366	$ 51	409	$ (1)
Private Tempest [Member]
Business Acquisition [Line Items]
Cash and Cash Equivalents, at Carrying Value					$ 17,000
Prepaid Expense and Other Assets					1,400
Accrued Liabilities and Other Liabilities					500
Operating Lease, Right-of-Use Asset					2,100
Operating Lease, Liability					$ 2,100
Private Tempest [Member] \| Additional Paid-in Capital [Member]
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	6,100		6,100
Private Tempest [Member] \| General and Administrative Expense [Member]
Business Acquisition [Line Items]
Share-based compensation expense	$ 200		$ 200