Employee Benefit Plans (Net Periodic Benefit Cost) (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011		Jun. 30, 2010
Pension Benefits [Member]
Service cost	$ 27	$ 25	$ 54		$ 52
Interest cost	65	68	129		134
Expected return on plan assets	(111)	(106)	(221)		(205)
Amortization of prior service cost (credit)	1	1	2		2
Amortization of net loss	24	15	48		30
Settlements and curtailments				[1]	84	[1]
Special termination benefits		1		[2]	10	[2]
Net periodic benefit cost	6	4	12		107
Other Postretirement Benefits [Member]
Service cost	12	14	24		28
Interest cost	24	25	47		50
Expected return on plan assets	(19)	(18)	(39)		(35)
Amortization of prior service cost (credit)	(4)	(1)	(7)		(3)
Amortization of net loss	3	3	6		6
Settlements and curtailments	(1)	(1)	(1)	[1]	37	[1]
Special termination benefits				[2]	1	[2]
Net periodic benefit cost	$ 15	$ 22	$ 30		$ 84

[1] 2010 amounts relate to the sale of Peoples and a workforce reduction program.

[2] Represents a one-time special termination benefit for certain employees in connection with a workforce reduction program.