OTHER FINANCIAL DATA - EARNINGS PER SHARE (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Earnings Per Share Numerator [Abstract]
Earnings	$ 178		$ 236
Earnings Per Share Denominator [Abstract]
Weighted-average common shares outstanding for basic EPS	243,294,000		240,566,000
Dilutive effect of stock options, restricted stock awards and restricted stock units	4,240,000		3,195,000
Weighted-average common shares outstanding for diluted EPS	247,534,000		243,761,000
Earnings Per Share [Abstract]
Basic earnings per common share	$ 0.73		$ 0.98
Diluted earnings per common share	$ 0.72		$ 0.97
Seventy Fifth Percentile Or Above [Member]
Total Shareholder Return Ranking [Line Items]
Common Shares Received For Each Restricted Stock Unit	1.5	[1]
Fiftieth Percentile [Member]
Total Shareholder Return Ranking [Line Items]
Common Shares Received For Each Restricted Stock Unit	1	[1]
Thirty Fifth Percentile Or Below [Member]
Total Shareholder Return Ranking [Line Items]
Common Shares Received For Each Restricted Stock Unit	0	[1]
Restricted Stock Units [Member]
Schedule Of Performance Based Restricted Shares [Line Items]
Contractual vesting percentage maximum	150.00%
Restricted Stock Awards [Member]
Schedule Of Performance Based Restricted Shares [Line Items]
Contractual vesting percentage maximum	100.00%
Out Of The Money Stock Options [Member]
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share			767,833
Restricted Stock
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	1,659,995		3,191,073
Restricted Stock Units
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	774
Restricted Stock Awards [Member]
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	3,090		15,932
San Diego Gas and Electric Company and Subsidiary [Member]
Earnings Per Share Numerator [Abstract]
Earnings	92		106
Southern California Gas Company [Member]
Earnings Per Share Numerator [Abstract]
Earnings	$ 46		$ 66

[1] Participants may also receive additional shares for dividend equivalents on shares subject to restricted stock units, which are reinvested to purchase additional units that become subject to the same vesting conditions as the restricted stock units to which the dividends relate.