New And Significant Accounting Policies (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned		$ 118	$ 96	$ 237	$ 195
Interest cost		169	173	337	346
Expected return on plan assets		(218)	(201)	(436)	(403)
Amortization of prior service cost		3	5	7	10
Amortization of net actuarial loss		3	1	6	1
Net periodic benefit cost		75	74	151	149
Less: transfer to regulatory account	[1]	9	9	18	19
Total		84	83	169	168
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned		14	11	27	22
Interest cost		18	19	36	38
Expected return on plan assets		(28)	(26)	(56)	(52)
Amortization of prior service cost		5	5	10	11
Amortization of net actuarial loss		1	1	2	1
Net periodic benefit cost		10	10	19	20
Less: transfer to regulatory account	[1]	0	0	0	0
Total		$ 10	$ 10	$ 19	$ 20

[1] The Utility recorded these amounts to a regulatory account since they are probable of recovery from customers in futures rates.