LIQUIDITY AND SIGNIFICANT ACCOUNTING POLICIES: (Narrative) (Details) (USD $) In Millions, unless otherwise specified			9 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Maximum
Summary of Significant Accounting Policies [Line Items]
Charge to be expensed, if an impairment of all the goodwill became necessary			$ 8.6
Valuation allowance against deferred tax assets (percent)	100.00%	100.00%

Represents the percentage of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

No definition available.

Name:	dlhc_DeferredTaxAssetsValuationAllowancePercentage
Namespace Prefix:	dlhc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant