| **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  2014   2013 Billed receivables     $2,569   $2,408 Unbilled receivables  (a)  9,803   9,535 Total accounts receivable     12,372   11,943 Less:  Allowance for doubtful accounts  (b)  —   — Accounts receivable, net     $12,372   $11,943 Ref (a):  Includes $9.3 million related to retroactive billings submitted to incorporate the impact of relevant wage determinations on certain contracts.  Revenues related to these retroactive billings were recognized in fiscal 2008 in accordance with GAAP, as follows:  (1) the Company developed and calculated an amount for such prior period services and had a contractual right to bill for such amounts under its arrangements, which was formalized in a contract modification (2) there were no remaining unfulfilled conditions for approval of such billings and (3) collectibility was reasonably assured based on historical practices with, and contractual requirements of, the DVA. The related direct costs, principally comprised of salaries and benefits, were accrued to match the recognized reimbursements from the Federal agency; upon approval, wages will be processed for payment to the employees.  During the year ended September 30, 2008, DLH recognized revenues of $10.8 million revenue related to these non-recurring adjustments, of which $1.5 million was subsequently billed and collected. DLH has had ongoing interactions with the customer during fiscal 2014, and in September 2014, we submitted a claim to the DVA to seek a final determination by the DVA’s contracting officer of the amount due to DLH and immediate payment of such amount. We expect closure on this issue within the next twelve months.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, 2014 and 2013. |
| Schedule of Other Current Assets                                                    |       (in thousands)      September 30, September 30,   Ref  2014   2013 Workers' compensation receivable  (a)  $199   $358 Prepaid insurance expense     176   143 Other prepaid expenses     135   98 Total other current assets     $510   $599 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 $0.2 million will be received within the next twelve months.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Schedule of Debt Obligations                                                        |       (in thousands)      September 30, September 30,   Ref  2014   2013 Bank loan payable     $—   $951 Current portion of capital lease obligation     —   22 Convertible debenture, net  (a)  —   340 Total debt obligations     $—   $1,313 Ref (a): See Note 12 regarding maturity and closure of the convertible debenture.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Schedule of Accrued Payroll                                                         |       (in thousands)      September 30, September 30,   Ref  2014   2013 Accrued current payroll     $2,440   $2,302 Accrued payroll related to unbilled accounts receivable    9,025   8,836 Total accrued payroll     $11,465   $11,138                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Equipment and Improvemnts, Net                                                      |       (in thousands)      September 30, September 30,   Ref  2014   2013 Furniture and equipment     $139   $139 Computer equipment     126   126 Computer software     430   417 Leasehold improvements     24   24       719   706 Less accumulated depreciation and amortization   (656)   (550) Equipment and improvements, net  (a)  $63   $156                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Accounts Payable, Accrued Expenses, and Other Current Liabilities                   | Accounts Payable, Accrued Expenses, and Other Current Liabilities      (in thousands)      September 30, September 30, Ref  2014   2013 Accounts payable     $779   $1,396 Accrued benefits     720   596 Accrued bonus and incentive compensation    693   860 Accrued workers compensation insurance     767   563 Other accrued expenses     339   534 Payroll tax accrual  (a)  1,448   1,394 Total accrued expenses and other current liabilities     $4,746   $5,343 Ref (a): From 2006 through 2009, DLH received notices from the Internal Revenue Service (“IRS”) claiming taxes, interest and penalties due related to payroll taxes.  These notices are predominantly related to the former PEO operations which were sold in fiscal 2003. The liability includes estimated accrued penalties and interest through the date of the financial statements totaling approximately $630 thousand.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Other Income (Expense)                                                              | Other Income (Expense)   (in thousands)    Year Ended    September 30,  Ref 2014 2013 Interest expense, net  $(99) $(172) Amortization of deferred financing costs  (10) (177) Change in value of derivative financial instruments(a) 99 (42) Other income (expense), net  6 (16) Total other expense, net  $(4) $(407) Ref (a): Represents the adjustment to fair value of embedded conversion feature and warrants related to the Company's convertible debentures.  Such instruments did not meet the requirements for qualified hedge accounting under GAAP.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5
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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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| - Definition
Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.
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Tabular disclosure of the carrying amounts of other current assets.
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