Pension and Other Postretirement Benefit Plans (Change in Plan Assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair Value of Plan Assets, end of year	$ 2,743	$ 2,460
United States Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair Value of Plan Assets, beginning of year	2,288	2,273
Actual return on plan assets	227	266
Employer contribution	303	41
Plan participants’ contributions
Gross benefits paid	(245)	(292)
Settlements
Foreign currency exchange rates
Fair Value of Plan Assets, end of year	2,573	2,288
Foreign Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair Value of Plan Assets, beginning of year	172	179
Actual return on plan assets	5	10
Employer contribution	25	26
Plan participants’ contributions	2	2
Gross benefits paid	(31)	(45)
Settlements	0	(1)
Foreign currency exchange rates	(3)	1
Fair Value of Plan Assets, end of year	170	172
Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair Value of Plan Assets, beginning of year
Actual return on plan assets
Employer contribution	64	57
Plan participants’ contributions	10	17
Gross benefits paid	(74)	(74)
Settlements
Foreign currency exchange rates
Fair Value of Plan Assets, end of year