CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Current portion of long-term debt	$ 1,464	$ 1,427	[1]
Property, plant and equipment, net	35,498	36,503	[1]
Long-term Debt and Capital Lease Obligations	$ 21,335	$ 16,445	[1]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	50,000,000	50,000,000
Common stock, shares authorized	750,000,000	750,000,000
Common stock, shares outstanding	274,000,000	251,000,000
Common stock, No par value (in dollars per share)	$ 0	$ 0
Otay Mesa VIE [Member]
Current portion of long-term debt	$ 287	$ 10
Property, plant and equipment, net	302	321
Long-term Debt and Capital Lease Obligations	0	284
San Diego Gas and Electric Company [Member]
Current portion of long-term debt	336	220	[1]
Property, plant and equipment, net	15,524	14,838	[1]
Long-term Debt and Capital Lease Obligations	$ 5,404	$ 5,335	[1]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	45,000,000	45,000,000
Preferred stock, shares issued	0	0
Common stock, shares authorized	255,000,000	255,000,000
Common stock, shares outstanding	117,000,000	117,000,000
Common stock, No par value (in dollars per share)	$ 0	$ 0
San Diego Gas and Electric Company [Member] | Otay Mesa VIE [Member]
Current portion of long-term debt	$ 287	$ 10
Property, plant and equipment, net	302	321
Long-term Debt and Capital Lease Obligations	0	284
Southern California Gas Company [Member]
Current portion of long-term debt	3	501	[1]
Property, plant and equipment, net	12,135	11,406	[1]
Long-term Debt and Capital Lease Obligations	$ 3,427	$ 2,485	[1]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares authorized	11,000,000	11,000,000
Preferred stock, shares issued	1,000,000	1,000,000
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares outstanding	91,000,000	91,000,000
Common stock, No par value (in dollars per share)	$ 0	$ 0
Convertible Preferred Stock Series A [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares issued	17,250,000	0
Preferred stock, shares outstanding	17,250,000	0
Convertible Preferred Stock Series B [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, shares issued	5,750,000	0
Preferred stock, shares outstanding	5,750,000	0

[1] Derived from audited financial statements.