Commitments and Contingencies (Undiscounted Future Minimum Expected Payments for Power Purchase Agreements) (Details) - Southern California Edison $ in Millions	Dec. 31, 2015 USD ($)
Renewable Energy Contracts
Power Purchase Agreements, Fiscal Year Maturity
2016	$ 1,234
2017	1,417
2018	1,472
2019	1,562
2020	1,605
Thereafter	21,439
Total future commitments	28,729
QF Power Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2016	223
2017	189
2018	149
2019	87
2020	39
Thereafter	69
Total future commitments	756
Other Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2016	741
2017	758
2018	589
2019	503
2020	459
Thereafter	1,022
Total future commitments	4,072
Signed contracts, not meeting critical contract provisions [Member]
Power Purchase Agreements, Fiscal Year Maturity
2016	29
2017	166
2018	257
2019	352
2020	747
Thereafter	$ 16,429