Pro forma information about actual expenses since the acquisition date.

No definition available.

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Namespace Prefix:	djco_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:	na
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=djco_ISDMember
Namespace Prefix:
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- Details

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Note 6 - Reportable Segments (Details Textual) (USD $)	12 Months Ended			1 Months Ended	10 Months Ended
Note 6 - Reportable Segments (Details Textual) (USD $)	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2013
Segment Reporting [Abstract]
Number of Reportable Segments		2us-gaap_NumberOfReportableSegments
Amortization of Intangible Assets	$ 4,866,000us-gaap_AmortizationOfIntangibleAssets	$ 1,865,000us-gaap_AmortizationOfIntangibleAssets	$ 0us-gaap_AmortizationOfIntangibleAssets
ISD Corporation [Member]
Segment Reporting [Abstract]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		784,000		784,000
Business Combination Pro Forma Information Expenses Since Acquisition Date Actual		694,000		694,000
Amortization of Intangible Assets		278,000		278,000
New Dawn [Member]
Segment Reporting [Abstract]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual					10,403,000
Business Combination Pro Forma Information Expenses Since Acquisition Date Actual					10,625,000
Amortization of Intangible Assets					$ 1,587,000