Consolidated Statements of Cash Flows (Unaudited) (Parentheticals) (USD $)	9 Months Ended
Jun. 30, 2012
Other-than-temporary impairment losses on investments, net of taxes (in Dollars)	$ 1,720,000

After-tax amount of the write-down of equity security (stocks) costs and are recognized in earnings

No definition available.

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