| **Supporting Financial Information (Tables)**                                       | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Organization, Consolidation and Presentation of Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Schedule of Accounts Receivable                                                     |       (in thousands)      September 30, September 30,   Ref  2015   2014 Billed receivables     $2,498   $2,569             Unbilled receivables-retroactive payment claim  (a)  —   9,306 Unbilled receivables-other     788   497 Total unbilled receivables     788   9,803             Total accounts receivable     3,286   12,372 Less:  Allowance for doubtful accounts  (b)  —   — Accounts receivable, net     $3,286   $12,372 Ref (a):  As previously reported, during the fiscal year ended September 30, 2008, DLH Holdings Corp. (the “Company”) accrued salaries and benefits of $10.1 million related to the estimated resolution of retroactive payment cases asserted by the Department of Labor (“DOL”).  During the same period, the Company recognized revenues of $10.8 million related to expected recovery of these costs, plus estimated indirect costs, under contractual arrangements with the Department of Veterans Affairs (“DVA”).  At September 30, 2014, the amount of the remaining accounts receivable with the DVA approximated $9.3 million and accrued liabilities for salaries to employees and related benefits totaled $8.7 million.  The $9.3 million in accounts receivable was unbilled to the DVA at September 30, 2014.  In September 2014, we submitted a claim to the DVA seeking a final determination and resolution of this matter.  During the quarter ended March 31, 2015, we were advised that the DOL would not take further action with respect to the retroactive payment cases and that it would not object to the DVA’s resolution of this matter with the Company.  As a result, we had no obligation for the payment of these accrued salaries and benefits.  Because no retroactive wage payments were required, we have no contractual recovery of costs from the DVA.  Accordingly, in order to resolve this matter, on March 30, 2015, we entered into a mutual release of claims with the DVA, pursuant to which both parties agreed to fully release each other from any and all claims arising pursuant to this matter.  As a result of the closure of this issue, as a part of our reporting for the quarter ended March 31, 2015, we removed the accruals of estimated revenue and expense which were recorded in the year ended September 30, 2008.  Further, we reported a reduction of $9.3 million in accounts receivable, a reduction of $8.7 million in accrued liabilities for salaries to employees and related benefits, and a net charge to our earnings of approximately $629 thousand for the fiscal quarter ended March 31, 2015 relating to the resolution of this matter.  The net expense related to this issue was non-cash and not related to income from current operations. Ref (b): Accounts receivable are unsecured and carried at fair value, which is net of an allowance for doubtful accounts.  We evaluate our receivables on a quarterly basis and determine whether an allowance is appropriate based on specific collection issues.  Our allowance for doubtful accounts was zero at both September 30, 2015 and 2014. |
| Schedule of Other Current Assets                                                    |       (in thousands)      September 30, September 30,   Ref  2015   2014 Workers’ compensation receivable  (a)  $29   $199 Prepaid insurance expense     156   176 Other prepaid expenses     244   135 Other current assets     $429   $510 Ref (a): As part of the Company’s discontinued PEO operations, DLH had a workers’ compensation program with Zurich American Insurance Company (“Zurich”) which covered the period from March 22, 2002 through November 16, 2003, inclusive. DLH estimates that the remaining workers compensation receivable of approximately $29 thousand will be received within the next twelve months.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Schedule of Accrued Payroll                                                         |       (in thousands)      September 30, September 30,   Ref  2015   2014 Accrued payroll related to billed receivables     $2,259   $2,440             Accrued payroll related to retroactive payment claim  (a)  $—   $8,677 Accrued payroll related to unbilled accounts receivable     $536   $348 Total accrued payroll related to unbilled accounts receivable  (a)  $536   $9,025             Total accrued payroll     $2,795   $11,465 Ref (a): Related to retroactive payment claim described above in “Accounts Receivable”.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Equipment and Improvemnts, Net                                                      |       (in thousands)      September 30, September 30,   Ref  2015   2014 Furniture and equipment     $197   $139 Computer equipment     162   126 Computer software     297   430 Leasehold improvements     63   24 Total fixed assets     719   719 Less accumulated depreciation and amortization   (383)   (656) Equipment and improvements, net  (a)  $336   $63 Ref (a): Equipment and improvements are stated at cost. Depreciation and amortization are provided using the straight-line method over the estimated useful asset lives (3 to 7) and the shorter of the initial lease term or estimated useful life for leasehold improvements.  Maintenance and repair costs are expensed as incurred.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Accounts Payable, Accrued Expenses, and Other Current Liabilities                   | Accounts Payable, Accrued Expenses, and Other Current Liabilities    (in thousands)    September 30, September 30, Ref  2015   2014 Accounts payable   $87   $779 Accrued benefits   267   720 Accrued bonus and incentive compensation   858   693 Accrued workers compensation insurance   945   767 Other accrued expenses   694   339 Payroll tax payable(a)  —   1,448 Total Accrued expenses and other current liabilities   $2,851   $4,746 Ref (a): In prior periods, DLH had received notices from the IRS claiming taxes, interest and penalties were due related to payroll taxes. These notices were predominantly related to the former PEO operations which were sold in fiscal year 2003. During fiscal year ended September 30, 2015, DLH engaged tax counsel who was able to demonstrate that there were no taxes due related to this legacy issue.  In September 2015, DLH received confirmation from the IRS that no taxes, interest, or penalties were due or otherwise payable.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Other Income (Expense)                                                              | Other Income (Expense)   (in thousands)   Year Ended   September 30, Ref 2015 2014Interest expense, net  $(80) $(99)Amortization of deferred financing costs  — (10)Change in value of financial instruments(a) — 99Miscellaneous other income (expense), net(b) 824 6Total other income (expense), net  $744 $(4)Ref (a): Represents the adjustment to fair value of embedded conversion feature and warrants related to the Company's convertible debentures in prior year ended September 30, 2014.Ref (b):  Current year miscellaneous other income includes $1.5 million from resolution of the legacy payroll tax issue in fourth quarter 2015, partially offset by the $0.6 million, net, March 2015 non-cash settlement of the retroactive payment issue.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |

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Other Income (Expense) [Table Text Block]
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Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
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Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables.
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Tabular disclosure of the (a) carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business (accounts payable); (b) other payables; and (c) accrued liabilities. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). An alternative caption includes accrued expenses.
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Tabular disclosure of the components of accrued liabilities.
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Tabular disclosure of the carrying amounts of other current assets.
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