Class of Warrant or Right, Exercise Period

No definition available.

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Namespace Prefix:	dlhc_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Related Party Transaction, Due to Related Party, Monthly Consulting Fee Paid

+ References

No definition available.

+ Details

Name:	dlhc_RelatedPartyTransactionDuetoRelatedPartyMonthlyConsultingFeePaid
Namespace Prefix:	dlhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Subordinated Lenders, Ownership Percentage of Equity

+ References

No definition available.

+ Details

Name:	dlhc_SubordinatedLendersOwnershipPercentageofEquity
Namespace Prefix:	dlhc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Warrants Issued in Consideration for Subordinated Loan, Percentage or Principal Amount

+ References

No definition available.

+ Details

Name:	dlhc_WarrantsIssuedinConsiderationforSubordinatedLoanPercentageorPrincipalAmount
Namespace Prefix:	dlhc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of warrants issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

Name:	us-gaap_DebtConversionConvertedInstrumentWarrantsOrOptionsIssued1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=dlhc_NotePurchaseAgreementwithWynnefieldPartnersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=dlhc_WynnefiledCapitalBankTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Related Party Transactions (Details) - USD ($)		9 Months Ended	12 Months Ended
Related Party Transactions (Details) - USD ($)	May 02, 2016	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	May 03, 2016
Related Party Transaction [Line Items]
Warrants issued in connection with subordinated debt			177,000	0
Note Purchase Agreement with Wynnefield Partners [Member]
Related Party Transaction [Line Items]
Warrants Issued in Consideration for Subordinated Loan, Percentage or Principal Amount	8.00%
Affiliated Entity [Member] \| Note Purchase Agreement with Wynnefield Partners [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Due to Related Party, Monthly Consulting Fee Paid					$ 10,000
Wynnefiled Capital, Bank Term Loan
Related Party Transaction [Line Items]
Warrants issued in connection with subordinated debt		53,619
Wynnefiled Capital, Bank Term Loan \| Note Purchase Agreement with Wynnefield Partners [Member]
Related Party Transaction [Line Items]
Subordinated Lenders, Ownership Percentage of Equity	42.00%
Warrants issued in connection with subordinated debt	53,619
Class of Warrant or Right, Exercise Period	5 years
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 3.73
Subordinated Debt \| Wynnefiled Capital, Bank Term Loan
Related Party Transaction [Line Items]
Debt face amount			$ 0		$ 2,500,000
Subordinated Debt \| Wynnefiled Capital, Bank Term Loan \| Note Purchase Agreement with Wynnefield Partners [Member]
Related Party Transaction [Line Items]
Debt face amount	$ 2,500,000.0