Note 9 - Stock-Based Compensation - Restricted Stock Awards (Details) - Restricted Stock [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Balance, number of shares (in shares)	20,118
Balance, weighted average grant date fair value (in dollars per share)	$ 5.22	$ 5.22
Balance, aggregate grant date fair value	$ 105	$ 105
Granted, number of shares (in shares)	0
Granted, weighted average grant date fair value (in dollars per share)	$ 0
Granted, aggregate grant date fair value	$ 0
Vested, number of shares (in shares)	0
Vested, weighted average grant date fair value (in dollars per share)	$ 0
Vested, aggregate grant date fair value	$ 0
Canceled, number of shares (in shares)	0
Canceled, weighted average grant date fair value (in dollars per share)	$ 0
Canceled, aggregate grant date fair value	$ 0
Balance, number of shares (in shares)	20,118