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Number of persons employed by the Entity

No definition available.

Name:	dei_EntityNumberOfEmployees
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Data Type:	xbrli:decimalItemType
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Represents the number of integrated revenue streams areas of the entity.

No definition available.

Name:	dlhc_EntityNumberofIntegratedRevenueStreams
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Data Type:	xbrli:integerItemType
Balance Type:	na
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Represents the period for which the entity has provided professional services to U.S. Government.

No definition available.

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Represents the term of the award granted to the entity.

No definition available.

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Represents the minimum number of locations the entity operates in as of the balance sheet date.

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 275
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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Name:	us-gaap_MajorCustomersAxis=dlhc_DepartmentOfVeteransAffairsMember
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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