v3.8.0.1
DOCUMENT AND ENTITY INFORMATION - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Feb. 22, 2018
Jun. 30, 2017
Document And Entity Information [Line Items]      
Entity Registrant Name Sempra Energy    
Entity Central Index Key 0001032208    
Document Type 10-K    
Document Period End Date Dec. 31, 2017    
Amendment Flag false    
Document Fiscal Year Focus 2017    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Filer Category Large Accelerated Filer    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Common Stock, Shares Outstanding   255,324,212  
Entity Public Float     $ 28,300
Trading Symbol SRE    
San Diego Gas and Electric Company [Member]      
Document And Entity Information [Line Items]      
Entity Public Float     0
Southern California Gas Company [Member]      
Document And Entity Information [Line Items]      
Entity Public Float     $ 0