Note 2 - Summary of Significant Accounting Policies - Weighted Average Common Shares (Details) - shares	3 Months Ended								12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Weighted average common shares outstanding–basic (in shares)	12,156,931	12,189,761	12,234,599	12,026,361	11,962,679	11,886,005	11,241,183	10,755,729	12,151,913	11,461,399
Unvested shares of restricted stock and employee stock options (in shares)									87,245	318,513
Weighted average common shares and common share equivalents outstanding–diluted (in shares)	12,216,344	12,251,712	12,330,280	12,158,297	12,122,099	12,212,317	11,696,569	11,088,664	12,239,158	11,779,912
Average number of potentially dilutive securities excluded from calculation (in shares)									612,794	140,079