Note 15 - Subsequent Events (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 04, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 30, 2022	Aug. 19, 2021
Common stock, par or stated value per share		$ 0.01	$ 0.01
Common stock warrants		805,202
Warrants exercise price		$ 2.38			$ 172.50
Proceeds from issuance of common stock and warrants		$ 14,401	$ 5,209
Payment of equity issuance costs		627	67
Warrants for additional gross cash proceeds		2,274	$ 99
Proceeds from exercise of warrants		$ 1,200
August Warrants [Member]
Common stock warrants		1,400,000
Warrants receivable		$ 1,400
Warrants for additional gross cash proceeds		3,680
Additional warrants exercised		$ 500
January 2023 Registered Direct Offering [Member] | Pre Funded Warrants [Member] | Subsequent Event [Member]
Warrants exercise price	$ 0.0001
January 2023 Registered Direct Offering and Private Placement [Member] | Subsequent Event [Member]
Issuance of stock during period, Shares	476,842
Common stock, par or stated value per share	$ 0.01
Shares Issued, Price Per Share (in dollars per share)	$ 2.375
Proceeds from issuance of common stock and warrants	$ 2,500
Net Proceeds	2,100
Payment of equity issuance costs	$ 400
January 2023 Registered Direct Offering and Private Placement [Member] | Pre Funded Warrants [Member] | Subsequent Event [Member]
Issuance of stock during period, Shares	37,000
Common stock warrants	2.3749
Private Placement [Member] | Subsequent Event [Member]
Warrants to purchase shares of common stock	1,052,631
Warrants exercise price	$ 2.375
Warrants and Rights Outstanding, Term (Year)	5 years
Private Placement [Member] | Pre Funded Warrants [Member] | Subsequent Event [Member]
Warrants to purchase shares of common stock	538,789
Warrants exercise price	$ 0.0001
Placement Agent Warrants [Member]
Warrants to purchase shares of common stock				63,158
Warrants exercise price				$ 2.9688
Warrants and Rights Outstanding, Term (Year)				5 years