Retirement Benefits and Trusteed Assets (Pension Plan - Benefits related to Qualified and Nonqualified Pension Plans Expected to be paid in the Next Ten Years) (Details) (Pension Plan [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2015	$ 210
2016	216
2017	223
2018	233
2019	239
2020 - 2024	1,264
Total Defined Benefit Pension Plan Expected Future Payments	$ 2,385