Note 6 - Stockholders' Equity and Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands						1 Months Ended				6 Months Ended	9 Months Ended		12 Months Ended
	Jul. 03, 2024	Mar. 28, 2024	Apr. 30, 2023	Jan. 01, 2023	Jun. 09, 2022	Mar. 31, 2024	Dec. 31, 2023	May 31, 2021	Nov. 30, 2017	Jun. 15, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2017	Dec. 31, 2021
Common Stock, Par or Stated Value Per Share (in dollars per share)											$ 0.001				$ 0.001
Equity Classified Subscription, Value											$ 47,700
Right Offering Deemed Dividend											47,700	$ 0
Proceeds from Warrant Exercises											1,536	$ 14,828
Time-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value											18,700
Performance-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value											300
Market-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value											$ 5,300
The 2017 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)														10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)														1,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)				1,200,000			1,375,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)														1,200,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent														4.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)											78,490
The 2017 Inducement Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)									10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)									1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)						2,000,000		1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)											1,642,626
The 2017 Inducement Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)									10 years
The 2017 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)														250,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)											450,000			450,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent														1.50%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)											445,779
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)											117,539
Share-Based Payment Arrangement, Tranche One [Member] | Time-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage											25.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)											1 year
Share-Based Payment Arrangement, Tranche One [Member] | The 2017 Inducement Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage									25.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)									1 year
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness			$ 65,000
Warrants Issued in 2024 Rights Offering [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		0.5
Rights Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)					1
Class of Warrant or Right, Proceeds Upon Exercise	$ 66,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 11				$ 2.05		$ 2.05						$ 2.05
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	5,999,999						7,317,072				5,857,680		7,317,072
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)							$ 0.01						$ 0.01
Class of Warrans or Right, Exercise Price, Percentage of Subscription Price for Units	110.00%
Warrants and Rights Outstanding, Term (Year)	5 years
Class of Warrant or Right, Percentage Required for Redemption							200.00%						200.00%
Class of Warrant or Right, Period of Written Notice for Exercise (Day)													30 days
Class of Warrant or Right, Exercise, Consecutive Trading Days (Day)													20 days
Class of Warrant or Right, Exercised During Period (in shares)										7,250,897			66,175
Proceeds from Warrant Exercises										$ 14,900
Class of Warrant or Right, Outstanding (in shares)												0
Rights Offering Warrants [Member] | Vesting of First Half [Member]
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)	$ 0.01
Class of Warrant or Right, Percentage Required for Redemption	150.00%
Class of Warrant or Right, Vesting, Stock Price Trigger (in dollars per share)	$ 16.5
Rights Offering Warrants [Member] | Vesting of Second Half [Member]
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)	$ 0.01
Class of Warrant or Right, Percentage Required for Redemption	200.00%
Class of Warrant or Right, Vesting, Stock Price Trigger (in dollars per share)	$ 22
The 2024 Right Offering [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Equity Offering, Units, Maximum Amount Authorized (in shares)		6,000,000
Equity Offering Units, Offering Value		$ 60,000
Shares Issued, Price Per Share (in dollars per share)		$ 10
Number of Shares Per Unit Issued (in shares)		1
Number of Warrants in Each Unit (in shares)		2
Share Price (in dollars per share)		$ 11.55
Equity Classified Subscription, Value		$ 47,700
Right Offering Deemed Dividend		$ 47,700
Rights Offering [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001				0.001
Equity Offering, Units, Maximum Amount Authorized (in shares)	6,000,000
Shares Issued, Price Per Share (in dollars per share)	$ 10				$ 2.05
Number of Shares Per Unit Issued (in shares)	1				1
Number of Warrants in Each Unit (in shares)	2
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)	0.5
Stock Issued During Period, Shares, New Issues (in shares)	5,999,998				7,317,072
Proceeds from Issuance of Common Stock	$ 60,000				$ 15,000
Equity Offering, Units, Sale of Units (in shares)					7,317,072
Number of Warrants Per Unit (in shares)					1
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)					7,317,072
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)					$ 0.01
Rights Offering [Member] | Robert W. Duggan [Member]
Percent of Offering Purchased	88.00%
Rights Offering [Member] | Board of Directors Chairman [Member]
Investment Owned, Percent of Net Assets					56.00%
Private Placement [Member] | Robert W. Duggan [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001
Shares Issued, Price Per Share (in dollars per share)			$ 6.51
Stock Issued During Period, Shares, New Issues (in shares)			10,022,937