Document And Entity Information - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Nov. 30, 2015	Mar. 31, 2015
Entity Registrant Name	DAILY JOURNAL CORPORATION
Entity Central Index Key	0000783412
Trading Symbol	djco
Current Fiscal Year End Date	--09-30
Entity Filer Category	Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Common Stock, Shares Outstanding (in shares)		1,380,746
Entity Public Float			$ 198,239
Document Type	10-K
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Amendment Flag	false