Revenue from Contracts with Customers - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($) segment	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($) segment	Dec. 31, 2024 USD ($)
Disaggregation of Revenue [Line Items]
Number of reportable segments \| segment	3	3	3	3
Revenue	$ 39,520	$ 47,630	$ 119,712	$ 138,113
Transaction price allocated to unsatisfied or partially satisfied performance obligations	0		0
Revenue recognized included in deferred revenue			1,300	2,900
Remaining unamortized contract costs	300		300		$ 200
Impairment recognized	0	0	0	0
Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Revenue	$ 1,100	$ 2,800	$ 4,800	$ 14,600

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

HARTE HANKS INC 10-Q