Employee Benefit Plans, Components of Net Periodic Benefit Costs (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Benefit Plans (Textual)
The percentage of the higher of the projected benefit obligation or market-related value of plan assets in excess of which net actuarial losses are amortized	10.00%
Pension Plans [Member]
Components of net periodic benefit cost:
Service cost	$ 137	$ 140	$ 104
Interest cost	86	93	85
Expected return on plan assets	(131)	(125)	(112)
Amortization of:
Prior service cost (credit)	(19)	3	2
Net actuarial loss	57	33	12
Special charges (credits)	(5)	(3)	4
Net periodic benefit cost	125	141	95
Other Postretirement Benefit Plans [Member]
Components of net periodic benefit cost:
Service cost	12	12	11
Interest cost	18	21	22
Expected return on plan assets	0	0	0
Amortization of:
Prior service cost (credit)	(14)	(23)	(23)
Net actuarial loss	0	1	2
Special charges (credits)	0	0	4
Net periodic benefit cost	$ 16	$ 11	$ 16