Note 13 - Earnings Per Share - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Net income (loss) attributable to SPAR Group, Inc.	$ (3,150)	$ 3,902
Weighted average common shares – basic (in shares)	23,555	23,333
Stock options and unvested restricted shares (in shares)	174	147
Convertible Series B Preferred Stock (in shares)	0	975
Weighted average common shares – diluted (in shares)	23,729	24,455
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.13)	$ 0.17
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.13)	$ 0.16