Note 3 - Procurement Contracts and Research Agreements (Details Textual) $ in Thousands				1 Months Ended	3 Months Ended							9 Months Ended		12 Months Ended	61 Months Ended	70 Months Ended	73 Months Ended
	Sep. 28, 2022 USD ($)	May 12, 2022 USD ($)	Sep. 10, 2018 USD ($)	Oct. 31, 2024 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2024 USD ($)	Jul. 18, 2024 USD ($)	Sep. 30, 2024 USD ($)	Aug. 31, 2024 USD ($)	Feb. 29, 2024 USD ($)	Oct. 31, 2023	Dec. 31, 2021 USD ($)	Jul. 31, 2019 USD ($)
Contract with Customer, Liability, Revenue Recognized												$ 7,100
The 19C BARDA Contract [Member]
Number of Courses to Be Delivered			1,488,000																	106,000
Number of Vials in a Course			14																	28
Government Contract, Value of Award					$ 602,500							602,500			$ 602,500		$ 602,500
Government Contract, Base Period, Value of Award for Delivery and Support Activities			$ 51,700		51,700							51,700			51,700		51,700
Government Contract Value Related To Exercised Options																$ 519,600
Government Contract, Value, Payments Currently Specified as Unexercised Options												31,200				$ 31,200
Base Period of Performance, Exercise of Options, Term (Year)			10 years
Government Contract, Base Period, Value of Award for Delivery and Support Activities, Delivery of Courses			$ 11,100
Government Contract, Base Period, Number of Deliveries			35,700
Government Contract, Base Period, Value of Award for Delivery and Support Activities, Manufacture of Courses			$ 8,000
Government Contract, Base Period, Value of Award for Delivery and Support Activities, Advanced Development			32,000
Government Contract, Base Period, Value of Award for Delivery and Support Activities, Supportive Procurement Activities			600
Proceeds from Delivery of Courses																	$ 11,100
Number of Courses Delivered																	35,700
Proceeds from Other Base Period Activities																	$ 24,700
Government Contract, Value, Payments Remaining Related to Exercised Options																	519,600
Government Contract, Value of Unexercised Options, Supportive Procurement Activities					5,600							5,600			5,600		5,600
The 19C BARDA Contract [Member] | Transferred over Time [Member]
Contract with Customer, Liability, Revenue Recognized					1,000			$ 200				3,800	$ 2,300
The 19C BARDA Contract [Member] | Transferred at Point in Time [Member]
Contract with Customer, Liability, Revenue Recognized					8,100			0				40,400	0
The 19C BARDA Contract [Member] | IV TPOXX [Member]
Number of Courses to Be Delivered																				10,000
Government Contract, Value, Payments Related to Exercised Options, Funding of Post-Marketing Activities					3,600							3,600			3,600		3,600
Government Contract, Value, Payments Related to Unexercised Options, Funding of Post-Marketing Activities					$ 10,200							$ 10,200			$ 10,200		$ 10,200
Number of Manufacturing Steps					2							2			2		2
The 19C BARDA Contract [Member] | IV TPOXX [Member] | Subsequent Event [Member]
Government Contract, Total Amount of Exercised Options, Delivery of Materials				$ 8,500
The 19C BARDA Contract [Member] | IV BDS [Member]
Government Contract, Base Period, Value of Award for Delivery and Support Activities, Manufacture of Courses			$ 3,200
Proceeds from the Manufacture of Courses																	$ 3,200
Proceeds from the Delivery of Courses																	4,800
Contract with Customer, Liability, Total					$ 9,000	$ 13,700	$ 20,500					$ 9,000			$ 9,000		$ 9,000				$ 3,200
Contract with Customer, Liability, Revenue Recognized						6,800
Government Contract, Number of Options for Manufacture of Product					3							3			3		3
Government Contract, Courses Manufactured Upon Exercise of Options					32,000							32,000			32,000		32,000
The 19C BARDA Contract [Member] | IV FDP Containing IV BDS [Member]
Contract with Customer, Liability, Total					$ 20,500							$ 20,500			$ 20,500		$ 20,500
Contract with Customer, Liability, Revenue Recognized						$ 300								$ 2,900
Government Contract, Value, Payments Currently Specified as Unexercised Options, Manufacture of Courses					$ 51,200							$ 51,200			$ 51,200		$ 51,200
The 19C BARDA Contract [Member] | Oral TPOXX [Member]
Number of Courses to Be Delivered					1,500,000							1,500,000			1,500,000		1,500,000
Government Contract, Value, Payments Related to Exercised Options, Delivery of Courses					$ 450,200							$ 450,200			$ 450,200		$ 450,200
Government Contract, Value, Payments Related to Exercised Options, Funding of Post-Marketing Activities					14,600							14,600			14,600		14,600
Government Contract, Total Amount of Exercised Options, Delivery of Materials					8,000		$ 15,000								345,800
The 19C BARDA Contract [Member] | Oral TPOXX [Member] | Subsequent Event [Member]
Government Contract, Total Amount of Exercised Options, Delivery of Materials				$ 51,200
The 19C BARDA Contract [Member] | IV FDP [Member]
Government Contract, Value, Payments Currently Specified as Unexercised Options, Manufacture of Courses					$ 25,600							$ 25,600			$ 25,600		$ 25,600
Government Contract, Number of Options for Manufacture of Product					3							3			3		3
Government Contract, Courses Manufactured Upon Exercise of Options					32,000							32,000			32,000		32,000
The 19C BARDA Contract [Member] | Maximum [Member]
Number of Courses to Be Delivered			212,000
IC BARDA [Member] | Transferred over Time [Member]
Government Contract, Value, Payments Currently Specified as Unexercised Options, Manufacture of Courses					$ 10,200							$ 10,200			$ 10,200		$ 10,200
Government Contract, Value, Payments Related to Unexercised Options, Funding of Post-Marketing Activities					25,600							25,600			$ 25,600		$ 25,600
U.S. Department of Defense (“DoD”) [Member] | Oral TPOXX [Member]
Government Contract, Value, Payments Currently Specified as Unexercised Options	$ 5,500	$ 3,800
Contract with Customer, Liability, Revenue Recognized									$ 5,100		$ 3,600
Government Contract, Value Ordered	$ 5,100	$ 3,600																$ 9,000	$ 1,000
Government Contract, Value, Option Exercised									$ 5,500	$ 3,800
International Procurement [Member] | Oral TPOXX [Member]
Contract with Customer, Liability, Revenue Recognized					800							11,800
International Procurement [Member] | Oral TPOXX [Member] | Transferred at Point in Time [Member]
Contract with Customer, Liability, Revenue Recognized					800			7,800				11,800	9,100
The PEP Label Expansion R & D Contract with the Department of Defense [Member]
Government Contract, Increased Value of Award																						$ 27,000
The PEP Label Expansion R & D Contract with the Department of Defense [Member] | Transferred over Time [Member]
Contract with Customer, Liability, Revenue Recognized					$ 0			$ 900				$ 0	$ 6,400