Document and Entity Information - shares shares in Thousands	9 Months Ended
	Sep. 30, 2019	Nov. 01, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Entity Registrant Name	American Shared Hospital Services
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		5,816
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Central Index Key	0000744825
Current Fiscal Year End Date	--12-31
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Small Business	true