| **Business Overview**                                                               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Organization, Consolidation and Presentation of Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Business Overview                                                                   | Business Overview DLH is a full-service provider of professional healthcare and social services to government agencies including the Department of Veteran Affairs ("VA"), Department of Health and Human Services ("HHS"), Department of Defense ("DoD"), and other government agencies. 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.  We employ over 1,400 skilled employees working in more than30 locations throughout the United States. On May 3, 2016, DLH acquired Danya International, LLC (“Danya”) which provides technology-enabled program management, consulting, and digital communications solutions to federal government and other customers. We acquired Danya to expand our ability to provide complementary business services and offerings across government markets. This acquisition is in line with our strategic growth initiatives, and we intend to continue to review and position ourselves for other potential joint venture or strategic acquisition opportunities in the future.The Company operates as a single business segment.  The foundations of our business offerings are now focused on three primary sources of revenue within the Federal health services market space, as follows:•Department of Defense and veteran health services, comprising approximately 54% of our current business base;•Human services and solutions, approximately 41% of our current business base; and•Public health and life sciences, approximately 5% of our current business base.  Presently, the Company derives 100% of its revenue from agencies of the Federal government, primarily as a prime contractor but also as a subcontractor to other Federal prime contractors.  A major customer is defined as a customer from whom the Company derives at least 10% of its revenues. Our largest customer continues to be the VA, which comprised approximately 83% and 95% of revenue for the nine months ended June 30, 2016 and 2015, respectively.  Additionally, HHS represents a major customer, comprising 13% of revenue for the nine months ended June 30, 2016 following the Danya acquisition. In addition, substantially all accounts receivable, including unbilled accounts receivable, are from agencies of the U.S. Government as of June 30, 2016 and 2015. We believe that the credit risk associated with our receivables is limited due to the creditworthiness of these customers. See Note 4, Supporting Financial Information-Accounts Receivable.As of June 30, 2016, awards from VA and HHS have anticipated periods of performance ranging from approximately one to up to four 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 VA and HHS under its current contracts, we believe that our strong working relationships 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 relationship with VA and HHS. |

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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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