Supplemental Cash Flows Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash payments (receipts) for interest and taxes:
Interest, net of amounts capitalized	$ 512	$ 504	$ 477
Tax payments (refunds), net	1	32	28
Details of debt exchange:
Pollution-control bonds redeemed (2.875%)	(203)	0	0
Pollution-control bonds issued (1.875%)	203	0	0
Notes issued under EME Settlement Agreement	0	418	0
Southern California Edison
Cash payments (receipts) for interest and taxes:
Interest, net of amounts capitalized	478	487	462
Tax payments (refunds), net	144	(88)	28
Details of debt exchange:
Pollution-control bonds redeemed (2.875%)	(203)	0	0
Pollution-control bonds issued (1.875%)	203	0	0
Notes issued under EME Settlement Agreement	0	0	0
Accrued capital expenditures	543	837	661
Reduction of lease obligations	(147)
Common Stock
Non-cash financing and investing activities:
Dividends declared but not paid:	156	136	116
Common Stock | Southern California Edison
Non-cash financing and investing activities:
Dividends declared but not paid:	0	147	0
Preference stock
Non-cash financing and investing activities:
Dividends declared but not paid:	14	18	30
Preference stock | Southern California Edison
Non-cash financing and investing activities:
Dividends declared but not paid:	$ 14	$ 18	$ 30
2.875% Pollution-Control Bonds [Member]
Other Significant Noncash Transactions [Line Items]
Debt Conversion, Original Debt, Interest Rate of Debt	2.875%	2.875%	2.875%
2.875% Pollution-Control Bonds [Member] | Southern California Edison
Other Significant Noncash Transactions [Line Items]
Debt Conversion, Original Debt, Interest Rate of Debt	2.875%	2.875%	2.875%
1.875% Pollution-Control Bonds Due in 2029
Other Significant Noncash Transactions [Line Items]
Debt Conversion, Original Debt, Interest Rate of Debt	1.875%	1.875%	1.875%
1.875% Pollution-Control Bonds Due in 2029 | Southern California Edison
Other Significant Noncash Transactions [Line Items]
Debt Conversion, Original Debt, Interest Rate of Debt	1.875%	1.875%	1.875%