Supplemental Cash Flows Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash payments for interest and taxes:
Interest, net of amounts capitalized	$ 152us-gaap_InterestPaidNet	$ 157us-gaap_InterestPaidNet
Tax payments (refunds), net	0us-gaap_IncomeTaxesPaidNet	0us-gaap_IncomeTaxesPaidNet
Common stock
Dividends declared but not paid:
Dividends declared but not paid	136	116
Preferred and preference stock
Dividends declared but not paid:
Dividends declared but not paid	3	4
Southern California Edison
Cash payments for interest and taxes:
Interest, net of amounts capitalized	144	149
Tax payments (refunds), net	32	3
Dividends declared but not paid:
Accrued capital expenditures	407	438
Southern California Edison \| Common stock
Dividends declared but not paid:
Dividends declared but not paid	147	126
Southern California Edison \| Preferred and preference stock
Dividends declared but not paid:
Dividends declared but not paid	$ 3	$ 4

Future cash outflow to pay for purchases of fixed assets that have occurred.

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