OTHER FINANCIAL DATA - EARNINGS PER SHARE (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share Numerator [Abstract]
Earnings	$ 296		$ 268	$ 719	$ 566
Earnings Per Share Denominator [Abstract]
Weighted-average common shares outstanding for basic EPS	244,140,000		241,689,000	243,682,000	241,133,000
Dilutive effect of stock options, restricted stock awards and restricted stock units	5,119,000		4,113,000	5,041,000	3,880,000
Weighted-average common shares outstanding for diluted EPS	249,259,000		245,802,000	248,723,000	245,013,000
Earnings Per Share [Abstract]
Basic earnings per common share	$ 1.21		$ 1.11	$ 2.95	$ 2.35
Diluted earnings per common share	$ 1.19		$ 1.09	$ 2.89	$ 2.31
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 minimum	0.00%
Contractual vesting percentage maximum	150.00%
Restricted Stock Awards [Member]
Schedule Of Performance Based Restricted Shares [Line Items]
Contractual vesting percentage minimum	0.00%
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	0		0	0	40,000
Restricted Stock
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	712,941		2,349,338	889,420	2,523,343
Restricted Stock Units
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0		3,387	0	1,881
Restricted Stock Awards [Member]
Antidilutive Securities Excluded From Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0		0	0	14,319
San Diego Gas and Electric Company and Subsidiary [Member]
Earnings Per Share Numerator [Abstract]
Earnings	134		176	292	378
Southern California Gas Company [Member]
Earnings Per Share Numerator [Abstract]
Earnings	$ 102		$ 71	$ 267	$ 191

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