Benefit Plans (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Pension Plans [Member]
Components of Net Periodic Benefit Cost
Service Cost	$ 18	$ 28	$ 54	$ 83
Interest Cost	59	63	178	190
Expected Return on Plan Assets	(79)	(78)	(236)	(234)
Amortization of Transition Obligation	0	0	0	0
Amortization of Prior Service Cost	1	0	1	0
Amortization of Net Actuarial Loss	31	22	92	67
Net Periodic Benefit Cost	30	35	89	106
Other Postretirement Benefit Plans [Member]
Components of Net Periodic Benefit Cost
Service Cost	11	12	32	35
Interest Cost	27	29	81	85
Expected Return on Plan Assets	(27)	(27)	(81)	(79)
Amortization of Transition Obligation	1	6	1	20
Amortization of Prior Service Cost	(1)	0	(1)	0
Amortization of Net Actuarial Loss	8	8	23	22
Net Periodic Benefit Cost	$ 19	$ 28	$ 55	$ 83