Note 4 - Collaboration and License Agreement 1 (Details Textual) - USD ($) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended	6 Months Ended	8 Months Ended
	Nov. 06, 2020	Apr. 30, 2021	Dec. 31, 2020	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2021
Contract with Customer, Liability, Current			$ 2,552	$ 4,010	$ 4,010	$ 4,010
Contract with Customer, Liability, Noncurrent			3,763	4,315	4,315	4,315
3D Medicines, Inc [Member]
Proceeds from Collaborators			$ 12,000	6,000	6,000	18,000
Collaborative Agreement, Maximum Clinical Development, Regulatory and Commercial Milestone Payments	$ 207,000
Collaborative Agreement, Royalty, Period After First Commercial Sale of Product (Year)	10 years
Revenue, Remaining Performance Obligation, Amount	$ 18,000
Contract with Customer, Liability, Revenue Recognized					800
Proceeds from Milestone Achievement		$ 6,000
Contract with Customer, Liability, Total				8,300	8,300	8,300
Contract with Customer, Liability, Current				4,000	4,000	4,000
Contract with Customer, Liability, Noncurrent				4,300	4,300	$ 4,300
3D Medicines, Inc [Member] | Research and Development Services [Member]
Revenue, Remaining Performance Obligation, Amount	9,600
Contract with Customer, Liability, Revenue Recognized				3,800	4,000
3D Medicines, Inc [Member] | License [Member]
Revenue, Remaining Performance Obligation, Amount	$ 8,400
Contract with Customer, Liability, Revenue Recognized				2,800	2,800
Proceeds from Milestone Achievement				6,000
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Estimate of Transaction Price				$ 3,200
Leland Stanford Junior University [Member]
Payments for License Agreement					$ 400