Pension and Other Postretirement Employee Benefit Plans - One Percentage Point Increase Effects (Details 7) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Effect of a one-percentage-point change in the assumed health care cost trend rate on the Firms total service and interest cost and accumulated postretirement benefit obligation
Effect on total service and interest cost, 1-Percentage-point increase	$ 1
Effect on total service and interest cost, 1-Percentage-point decrease	(1)
Effect on accumulated postretirement benefit obligation, 1-Percentage-point increase	28
Effect on accumulated postretirement benefit obligation, 1-Percentage-point decrease	(25)
Defined Benefit Pension Plans, U.S. [Member]
Effect of a one-percentage-point change in the assumed health care cost trend rate on the Firms total service and interest cost and accumulated postretirement benefit obligation
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets	7.50%	7.50%	7.50%
Projected Increase in US Defined Benefit Pension Plan Expense Resulting From a 25 Basis Point Increase in the Interest Crediting Rate for the US Plans	25
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Effect of a one-percentage-point change in the assumed health care cost trend rate on the Firms total service and interest cost and accumulated postretirement benefit obligation
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets	6.25%	6.25%	7.00%
US Pension Plans and Other US Postretirement Employee Benefit Plans [Member]
Effect of a one-percentage-point change in the assumed health care cost trend rate on the Firms total service and interest cost and accumulated postretirement benefit obligation
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year	7.00%	7.00%	7.75%
Defined Benefit Plan, Interest Crediting Rate		5.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	4.00%	4.00%	4.00%
Projected Increase in US Defined Benefit Pension and OPEB Plan Expense Resulting From a 25 Basis Point Decline in Expected Long-Term Rate of Return on US Plan Assets	35
Projected Increase in US Defined Benefit Pension and OPEB Plan Expense Resulting from a 25 Basis Point Decline in Discount Rate For US Plans	19
Projected Increase in US Defined Benefit Pension and OPEB Benefit Obligations Resulting from a 25-Basis Point Decline in the Discount Rate for the US Plans	272
Projected Increase In US Defined Benefit Pension Benefit Obligations Resulting From A25 Basis Boint Increase In Interest Crediting Rate For US Defined Benefit Pension Plan	116
Foreign Pension Plans and Other Foreign Postretirement Benefit Plans [Member]
Effect of a one-percentage-point change in the assumed health care cost trend rate on the Firms total service and interest cost and accumulated postretirement benefit obligation
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year	0.00%	0.00%	0.00%
Projected increase in non-U.S. defined benefit pension and OPEB plan expense resulting from a 25-basis point decline in the discount rate for the non-U.S. plans	$ 14