Note 6 - Per Share Amounts - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net income attributable to American Shared Hospital Services	$ 119,000	$ 188,000
Weighted average common shares for basic earnings per share (in shares)	6,452,000	6,306,000
Dilutive effect of stock options and restricted stock awards (in shares)	124,000	166,000
Weighted average common shares for diluted earnings per share (in shares)	6,576,000	6,472,000
Basic earnings per share (in dollars per share)	$ 0.02	$ 0.03
Diluted earnings per share (in dollars per share)	$ 0.02	$ 0.03