| **Business Overview**                                                               | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Organization, Consolidation and Presentation of Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Business Overview                                                                   | Business Overview For more than 25 years, DLH Holdings Corp. ("DLH"), has provided professional services to the U.S. Government. Headquartered in Atlanta, Georgia, DLH employs over 1,250 skilled technicians, logisticians, engineers, healthcare and support personnel at more than 30 locations around the United States. DLH’s operating subsidiary, DLH Solutions, Inc., provides services and solutions in two major market areas: Healthcare Delivery Solutions and Logistics & Technical Services. Our government customers, a majority of whom are within the Departments of Veterans Affairs (“DVA”) and Defense (“DoD”), benefit from our proven leadership, processes, technical excellence, industry-leading productivity and affordability enhancement tools, and Lean Six Sigma-based quality improvement processes. The remaining portion of DLH’s business is comprised of customers within other Federal agencies, including the Departments of Interior, Justice, and Agriculture at locations throughout the United States.DLH Holdings Corp. (together with its subsidiaries, "DLH" or the "Company" and also referred to as "we," "us" and "our") manages its operations from its principal executive offices at 3565 Piedmont Road NE, Building 3 Suite 700, Atlanta Georgia 30305.Presently, the Company derives all of its revenue from agencies of the federal government. A major customer is defined as a customer from whom the Company derives at least 10% of its revenues. In each of the fiscal years ended September 30, 2015 and 2014, revenue from the U.S. Government accounted, either directly or indirectly, for 100% of the Company’s total revenue.  Within the U.S. Government, our largest customer continues to be the Department of Veterans Affairs (DVA), at 95% and 96% of revenue for the twelve months ended September 30, 2015 and 2014.  In addition, substantially all accounts receivable, including unbilled accounts receivable, are from agencies of the U.S. Government as of September 30, 2015 and 2014.  We believe that the credit risk associated with our receivables is limited due to the credit worthiness of these customers.Accordingly, DLH remains dependent upon the continuation of its relationship with the DVA.  As of September 30, 2015, contracts with the DVA have anticipated periods of performance ranging from approximately one to up to three years.  These agreements are subject to the Federal Acquisition Regulations. While there can be no assurance as to the actual amount of services that the Company will ultimately provide to the DVA under its current contract, we believe that our strong working relationship and our effective service delivery support ongoing performance for the contract term. The Company's results of operations, cash flows and financial condition would be materially adversely affected in the event that we were unable to continue our relationships with the DVA. |

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| - Definition
The entire disclosure for the general note to the financial statements for the reporting entity which may include, descriptions of the basis of presentation, business description, significant accounting policies, consolidations, reclassifications, new pronouncements not yet adopted and changes in accounting principles.
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