DOCUMENT AND ENTITY INFORMATION - shares	9 Months Ended
	Sep. 30, 2018	Nov. 01, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Sempra Energy
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Shares Outstanding		273,660,222
Entity Central Index Key	0001032208
Trading Symbol	SRE