Employee Postretirement Benefits (Defined Contribution Pension Plans) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Costs charged to expense for defined contribution pension plans	$ 108	$ 113	$ 98
United States Pension Plans of US Entity, Defined Benefit [Member]
Costs charged to expense for defined contribution pension plans	82	77	75
Outside the U.S. [Member]
Costs charged to expense for defined contribution pension plans	$ 26	$ 36	$ 23