Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2024	Oct. 31, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Document Transition Report	false
Entity File Number	001-07120
Entity Registrant Name	HARTE HANKS, INC.
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	1 Executive Drive
Entity Address, City or Town	Chelmsford
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01824
Entity Tax Identification Number	74-1677284
City Area Code	512
Local Phone Number	434-1100
Title of 12(b) Security	Common Stock
Trading Symbol	HHS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		7,288,983
Entity Central Index Key	0000045919
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3