Consolidated Statements of Changes in Equity (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	$ 11,191	$ 11,086
Net income	298	112
Other comprehensive income (loss)	0	21
Contributions from noncontrolling interests		238
Transfer of assets to Capistrano Wind Partners		(50)
Common stock dividends declared	(110)	(106)
Dividends, distributions to noncontrolling interests and other	(27)	(16)
Stock-based compensation and other	(32)	(28)
Noncash stock-based compensation and other	2	5
Issuance of preference stock	387	345
Redemption of preference stock	(400)
Balance, at the end of the period	11,309	11,607
Dividends declared per common share (in dollars per share)	$ 0.3375	$ 0.325
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	2,373	2,360
Net income	0	0
Other comprehensive income (loss)		0
Contributions from noncontrolling interests		0
Transfer of assets to Capistrano Wind Partners		(50)
Common stock dividends declared	0	0
Dividends, distributions to noncontrolling interests and other	0	0
Stock-based compensation and other	1	8
Noncash stock-based compensation and other	6	7
Issuance of preference stock	0	0
Redemption of preference stock	0
Balance, at the end of the period	2,380	2,325
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	(87)	(139)
Net income	0	0
Other comprehensive income (loss)		21
Contributions from noncontrolling interests		0
Transfer of assets to Capistrano Wind Partners		0
Common stock dividends declared	0	0
Dividends, distributions to noncontrolling interests and other	0	0
Stock-based compensation and other	0	0
Noncash stock-based compensation and other	0	0
Issuance of preference stock	0	0
Redemption of preference stock	0
Balance, at the end of the period	(87)	(118)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	7,146	7,834
Net income	271	93
Other comprehensive income (loss)		0
Contributions from noncontrolling interests		0
Transfer of assets to Capistrano Wind Partners		0
Common stock dividends declared	(110)	(106)
Dividends, distributions to noncontrolling interests and other	0	0
Stock-based compensation and other	(33)	(36)
Noncash stock-based compensation and other	(4)	(2)
Issuance of preference stock	0	0
Redemption of preference stock	(8)
Balance, at the end of the period	7,262	7,783
Subtotal
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	9,432	10,055
Net income	271	93
Other comprehensive income (loss)		21
Contributions from noncontrolling interests		0
Transfer of assets to Capistrano Wind Partners		(50)
Common stock dividends declared	(110)	(106)
Dividends, distributions to noncontrolling interests and other	0	0
Stock-based compensation and other	(32)	(28)
Noncash stock-based compensation and other	2	5
Issuance of preference stock	0	0
Redemption of preference stock	(8)
Balance, at the end of the period	9,555	9,990
Other Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period		2
Net income		0
Other comprehensive income (loss)		0
Contributions from noncontrolling interests		238
Transfer of assets to Capistrano Wind Partners		0
Common stock dividends declared		0
Dividends, distributions to noncontrolling interests and other		3
Stock-based compensation and other		0
Noncash stock-based compensation and other		0
Issuance of preference stock		0
Balance, at the end of the period		243
Preferred Stock and Preference Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	1,759	1,029
Net income	27	19
Other comprehensive income (loss)		0
Contributions from noncontrolling interests		0
Transfer of assets to Capistrano Wind Partners		0
Common stock dividends declared	0	0
Dividends, distributions to noncontrolling interests and other	(27)	(19)
Stock-based compensation and other	0	0
Noncash stock-based compensation and other	0	0
Issuance of preference stock	387	345
Redemption of preference stock	(392)
Balance, at the end of the period	1,754	1,374
Southern California Edison
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	11,743	9,958
Net income	283	201
Other comprehensive income (loss)	(3)	3
Common stock dividends declared	(120)	(116)
Dividends declared on preferred and preference stock	(27)	(19)
Stock-based compensation and other	(29)	(15)
Noncash stock-based compensation and other	8	6
Issuance of preference stock	387	345
Redemption of preference stock	(400)
Balance, at the end of the period	11,842	10,363
Southern California Edison | Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	2,168	2,168
Net income	0	0
Other comprehensive income (loss)	0	0
Common stock dividends declared	0	0
Dividends declared on preferred and preference stock	0	0
Stock-based compensation and other	0	0
Noncash stock-based compensation and other	0	0
Issuance of preference stock	0	0
Redemption of preference stock	0
Balance, at the end of the period	2,168	2,168
Southern California Edison | Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	581	596
Net income	0	0
Other comprehensive income (loss)	0	0
Common stock dividends declared	0	0
Dividends declared on preferred and preference stock	0	0
Stock-based compensation and other	0	6
Noncash stock-based compensation and other	3	3
Issuance of preference stock	(13)	(5)
Redemption of preference stock	8
Balance, at the end of the period	579	600
Southern California Edison | Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	(29)	(24)
Net income	0	0
Other comprehensive income (loss)	(3)	3
Common stock dividends declared	0	0
Dividends declared on preferred and preference stock	0	0
Stock-based compensation and other	0	0
Noncash stock-based compensation and other	0	0
Issuance of preference stock	0	0
Redemption of preference stock	0
Balance, at the end of the period	(32)	(21)
Southern California Edison | Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	7,228	6,173
Net income	283	201
Other comprehensive income (loss)	0	0
Common stock dividends declared	(120)	(116)
Dividends declared on preferred and preference stock	(27)	(19)
Stock-based compensation and other	(29)	(21)
Noncash stock-based compensation and other	5	3
Issuance of preference stock	0	0
Redemption of preference stock	(8)
Balance, at the end of the period	7,332	6,221
Southern California Edison | Preferred Stock and Preference Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, at the beginning of the period	1,795	1,045
Net income	0	0
Other comprehensive income (loss)	0	0
Common stock dividends declared	0	0
Dividends declared on preferred and preference stock	0	0
Stock-based compensation and other	0	0
Noncash stock-based compensation and other	0	0
Issuance of preference stock	400	350
Redemption of preference stock	(400)
Balance, at the end of the period	$ 1,795	$ 1,395