Document And Entity Information In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Apr. 20, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	HEALTHCARE SERVICES GROUP INC
Entity Central Index Key	0000731012
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Amendment Flag	false
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		71,485