Basis of Presentation (Policies)	6 Months Ended
Basis of Presentation (Policies)	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation	Consolidation The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of Harte Hanks, Inc. and subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. As used in this report, the terms “Harte Hanks,” “the company,” “we,” “us,” or “our” may refer to Harte Hanks, Inc., one or more of its consolidated subsidiaries, or all of them taken as a whole.
Interim Financial Information	Interim Financial Information The financial statements have been prepared in accordance with U.S. Generally Accepted Accounting Principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. Operating results for the three and six months ended June 30, 2016 are not necessarily indicative of the results that may be expected for the year ending December 31, 2016. The information included in this Form 10-Q should be read in conjunction with Management’s Discussion and Analysis of Financial Condition and Results of Operations and the consolidated financial statements and notes thereto included in our annual report on Form 10-K for the year ended December 31, 2015.
Discontinued Operations	Discontinued Operations As discussed in Note M, Discontinued Operations, the operating results of our Trillium Software ("Trillium") reporting unit are classified as held for sale and reported as discontinued operations for all periods presented in the Condensed Consolidated Financial Statements. Unless otherwise stated, amounts related to the Trillium Software operations are excluded from the Notes to Condensed Consolidated Financial Statements for all periods presented. Results of the remaining Harte Hanks business are reported as continuing operations.
Reclassifications	Reclassifications Certain amounts in the financial statements for the prior years have been reclassified to conform to the current year's presentation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results and outcomes could differ from those estimates and assumptions. On an ongoing basis, management reviews its estimates based on currently available information. Changes in facts and circumstances could result in revised estimates and assumptions.
Operating Expense Presentation in Consolidated Statements of Comprehensive Income (Loss)	Operating Expense Presentation in Consolidated Statements of Comprehensive Income (Loss) “Labor” in the Consolidated Statements of Comprehensive Income (Loss) includes all employee payroll and benefits, including stock-based compensation, along with temporary labor costs. “Production and distribution” and “Advertising, selling, general and administrative” do not include labor, depreciation, or amortization.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2016 the FASB issued ASU 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-based Payment Accounting, which requires entities with share-based payment awards to recognize all related excess tax benefits and tax deficiencies as income tax expenses or benefit in the income statement. This ASU is effective for interim and annual periods beginning after December 15, 2016. Early adoption is permitted. We are evaluating the effect that this will have on our consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU 2016-02, Leases, which requires all operating leases to be recorded on the balance sheet. The lessee will record a liability for its lease obligations (initially measured at the present value of the future lease payments not yet paid over the lease term, and an asset for its right to use the underlying asset equal to the lease liability, adjusted for lease payments made at or before lease commencement). This ASU is effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. We are evaluating the effect that this will have on our consolidated financial statements and related disclosures. In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs, which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The ASU is effective for annual periods beginning after December 15, 2015, and interim periods within those annual periods. As a result, in conjunction with the closing of the 2016 Term Facility and 2016 Revolving Credit Facility, we recorded $2.2 million in unamortized debt discount and debt issuance costs as a reduction of the total debt balance. We also reclassified $0.2 million in unamortized debt issuance costs as a reduction of the debt balance as of December 31, 2015 that were previously included in Other Assets (see Note E, Long-Term Debt). In April 2015, the FASB issued ASU 2015-05, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement, which provides explicit guidance to help companies evaluate the accounting for fees paid by a customer in a cloud computing arrangement. This ASU is effective for interim and annual periods beginning after December 15, 2015. The adoption of this ASU did not have a material impact on our consolidated financial statements. In January 2015, the FASB issued ASU 2015-01, Income Statement - Extraordinary and Unusual Items (Subtopic 225-20): Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items, which eliminates the concept of extraordinary items from U.S. GAAP as part of its simplification initiative. The ASU does not affect disclosure guidance for events or transactions that are unusual in nature or infrequent in their occurrence. The ASU is effective for interim and annual periods in fiscal years beginning after December 15, 2015. The ASU allows prospective or retrospective application. Early adoption is permitted if applied from the beginning of the fiscal year of adoption. The adoption of this ASU did not have a material impact on our consolidated financial statements; however, future impact on the company will be dependent on any transaction or event that is within the scope of the new guidance. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard permits the use of either the retrospective or cumulative effect transition method. On July 9, 2015, the FASB decided to delay the effective date of the new revenue standard by one year. The new effective date is for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. Early adoption is permitted beginning January 1, 2017 (original effective date of the ASU). We are evaluating the effect that ASU 2014-09 and the related clarifying updates will have on our consolidated financial statements and related disclosures. We have not yet selected a transition method nor have we determined the effect of the standard on our ongoing financial reporting.