Pension Savings And Other Postretirement Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		1 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended				6 Months Ended	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Mar. 31, 2013 Frozen United States Pension Plans of US Entity, Defined Benefit [Member]	Feb. 28, 2013 Frozen United States Pension Plans of US Entity, Defined Benefit [Member]	Dec. 31, 2012 Frozen United States Pension Plans of US Entity, Defined Benefit [Member]	Jun. 30, 2013 U.S.	Jun. 30, 2012 U.S.	Jun. 30, 2013 U.S.	Jun. 30, 2012 U.S.	Jun. 30, 2013 Foreign Pension Plans, Defined Benefit	Jun. 30, 2012 Foreign Pension Plans, Defined Benefit	Jun. 30, 2013 Foreign Pension Plans, Defined Benefit	Jun. 30, 2012 Foreign Pension Plans, Defined Benefit	Aug. 31, 2012 Canadian Other Postretirement Benefit Plans, Change in Benefit Obligation [Member] Other Postretirement Benefit Plans, Defined Benefit [Member]	Aug. 31, 2012 U.S. Other Postretirement Benefit Plans, Change in Benefit Obligation [Member] Other Postretirement Benefit Plans, Defined Benefit [Member]	Jun. 30, 2013 Required Contributions [Member]	Mar. 31, 2013 Required Contributions [Member] Frozen United States Pension Plans of US Entity, Defined Benefit [Member]	Mar. 31, 2013 Discretionary Contributions [Member] Frozen United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost- benefits earned during the period								$ 12	$ 10	$ 23	$ 20	$ 10	$ 7	$ 20	$ 15
Interest cost on projected benefit obligation								60	65	121	131	32	35	65	70
Expected return on plan assets								(84)	(75)	(168)	(150)	(28)	(29)	(56)	(59)
Amortization of prior service cost								5	6	9	12	1	1	1	1
Amortization of net losses								50	43	103	89	14	11	30	23
Net periodic pension cost												29	25	60	50
Curtailments/settlements/termination benefits												2	0	2	0
Total defined benefit pension cost								43	49	88	102	31	25	62	50
Pension Savings and Other Postretirement Benefit Plans (Textuals) [Abstract]
Contributions to pension plans								50		918		26		56					34	834
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax						93
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate						3.82%	3.61%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets					4.75%
Defined Benefit Plan, Fair Value of Plan Assets						2,072
Expected Current Year Contributions To Funded Pension Plans, Minimum																		275
Expected Current Year Contributions To Funded Pension Plans, Maximum																		325
Expense recognized for contributions to defined savings plans	23	23	49	50
Postretirement benefit cost (credit)	(2)	0	(4)	3
Defined Benefit Plan, Benefit Obligation																$ 18	$ 56