Note 6 - Fair Value Measurements - Summary of Financial Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Inputs, Level 1 [Member] | Warrant Liability [Member]
Liabilities	$ 0	$ 0
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member]
Assets	20,023	43,574
Fair Value, Inputs, Level 1 [Member] | Restricted Cash [Member]
Assets	2,172	3,055
Fair Value, Inputs, Level 2 [Member] | Warrant Liability [Member]
Liabilities	0	0
Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member]
Assets	0	0
Fair Value, Inputs, Level 2 [Member] | Restricted Cash [Member]
Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Warrant Liability [Member]
Liabilities	1,033	3,473
Fair Value, Inputs, Level 3 [Member] | Cash and Cash Equivalents [Member]
Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Restricted Cash [Member]
Assets	$ 0	$ 0