Employee Benefit Plans Level 4 (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Benefits [Member]
Component of periodic benefit cost
Defined Benefit Plan, Service Cost	$ 0	$ 1	$ 1	$ 2
Interest cost	60	67	177	194
Expected return on plan assets	(77)	(81)	(233)	(244)
Amortization of prior service credit	0	0	0	0
Amortization of actuarial loss	16	13
Net periodic benefit cost	(1)	0	(10)	(13)
Defined Benefit Plan, Amortization of Gains (Losses)			(45)	(35)
Other Postretirement Benefits [Member]
Component of periodic benefit cost
Defined Benefit Plan, Service Cost	0	0	0	0
Interest cost	3	5	9	11
Expected return on plan assets	(3)	(2)	(9)	(10)
Amortization of prior service credit	(2)	(2)	(5)	(5)
Amortization of actuarial loss	1	1
Net periodic benefit cost	$ (1)	$ 2	(2)	(1)
Defined Benefit Plan, Amortization of Gains (Losses)			$ (3)	$ (3)