Employee Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 0	$ 0	$ 0	$ 0
Interest Cost	215	232	430	464
Expected Return on Plan Assets	(184)	(176)	(368)	(352)
Amortization of Prior Service Benefit	0	0	0	0
Recognized net actuarial loss	55	36	111	72
Settlements	0	0	6	0
Net periodic cost	86	92	179	184
Other Postretirement and Postemployment Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	12	14	24	29
Interest Cost	36	41	72	82
Expected Return on Plan Assets	(21)	(19)	(42)	(38)
Amortization of Prior Service Benefit	(7)	(6)	(14)	(9)
Recognized net actuarial loss	6	6	12	12
Settlements	0	104	0	104
Net periodic cost	$ 26	$ 140	$ 52	$ 180