Income Taxes (Deferred Income Tax Assets (Liabilities)) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Income Tax Expense (Benefit) [Abstract]
Pension and other postretirement benefits	$ 972	$ 756
Tax credits and loss carryforwards	729	812
Deferred Tax Assets, Tax Deferred Expense, Property, Plant and Equipment	110	128
Other	492	562
Deferred Tax Assets, Gross	2,303	2,258
Deferred Tax Assets, Valuation Allowance	(215)	(229)
Deferred Tax Assets, Net	2,088	2,029
Deferred Tax Liability Noncurrent Pension Postretirement And Other Employee Benefits	(269)	(206)
Property, plant and equipment, net	(1,228)	(1,305)
Installment sales	(120)	(119)
Deferred Tax Liabilities, Undistributed Foreign Earnings	(108)	(58)
Other	(385)	(365)
Deferred Tax Liabilities	(2,110)	(2,053)
Deferred Tax Assets (Liabilities), Net	$ (22)	$ (24)