| **Income Taxes (Tables)**                                                                                                            | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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| **Income Tax Disclosure [Abstract]**                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Schedule of analysis of deferred tax asset and liability                                                                             | An analysis of DLH's deferred tax asset and liability is as follows:  Year Ended  September 30,(amounts in thousands) 2015 2014Current deferred income tax asset:    Net operating loss carryforwards and tax credits $391 $98Accrued liabilities 753 122Valuation allowance (162) (136)Net current deferred tax asset $982 $84  Year Ended  September 30,(amounts in thousands) 2015 2014Deferred income tax asset (liability):    Net operating loss carry forwards and tax credits $12,524 $16,556Stock based compensation 767 646Fixed and intangible assets (2,379) (2,176)Other items, net 5 488Valuation allowance (1,592) (11,001)Net deferred tax asset $9,325 $4,513 |
| Summary of significant components of the expense (benefit) for income taxes from continuing operations                               | The significant components of the expense (benefit) for income taxes from continuing operations are summarized as follows:  Year Ended  September 30,(amounts in thousands) 2015 2014Current expense (benefit) $220 $7Deferred expense (benefit) (5,708) (4,604)Total expense (benefit) $(5,488) $(4,597)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Schedule of significant differences between the Federal statutory rate and the entity's effective tax rate for continuing operations | The following table indicates the significant differences between the federal statutory rate and DLH's effective tax rate for continuing operations:  Year Ended  September 30,(amounts in thousands) 2015 2014Federal statutory rate $1,134 $258State taxes, net 155 46Other permanent items 7 6Change in valuation allowance (6,784) (4,907)  $(5,488) $(4,597)                                                                                                                                                                                                                                                                                                                                                                                                                                 |

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| - Definition
Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319
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| - Definition
Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319
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| - Definition
Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.
+ References
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