Document and Entity Information - Jun. 30, 2015 - shares	Total
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2
Trading Symbol	DTIPIV
Entity Registrant Name	DEL TACO INCOME PROPERTIES IV
Entity Central Index Key	0000812630
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	165,375