Employee Benefit Plans Employee Benefit Plans (Net Periodic Defined Benefit Cost) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Net periodic defined benefit cost			$ 29	$ 65
Defined Benefit Pension Plans | Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	7	9	22	28
Interest cost	22	20	66	59
Expected return on plan assets	(33)	(33)	(99)	(99)
Amortization of prior service cost (credit)	1	1	4	3
Amortization of net loss	9	18	24	56
Net periodic defined benefit cost	6	15	17	47
Defined Benefit Pension Plans | Non-Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	3	3
Interest cost	2	2	7	7
Amortization of prior service cost (credit)	(1)	0	(3)	(1)
Amortization of net loss	2	3	5	8
Net periodic defined benefit cost	4	6	12	17
Postretirement Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0	1	2	3
Expected return on plan assets	(1)	(1)	(3)	(3)
Amortization of net loss	1	0	1	1
Net periodic defined benefit cost	$ 0	$ 0	$ 0	$ 1