Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Feb. 15, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	0-12015
Entity Registrant Name	HEALTHCARE SERVICES GROUP, INC.
Entity Incorporation, State Code	PA
I.R.S. Employer Identification No.	23-2018365
Entity Address, Address Line One	3220 Tillman Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Bensalem
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19020
City Area Code	215
Local Phone Number	639-4274
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	HCSG
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,060
Entity Common Stock, Shares Outstanding		74,390,448
Documents Incorporated by Reference	Portions of the definitive Proxy Statement for the Registrant’s Annual Meeting of Shareholders to be held on May 30, 2023 have been incorporated by reference into Parts II and III of this Annual Report on Form 10-K.
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Entity Central Index Key	0000731012