Property, Plant and Equipment (Depreciation Expense, Software Amortization and Capitalized Interest) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Abstract]
Depreciation expense (including amortization of assets recorded under capital leases)	$ 1,193	$ 1,173	$ 1,078
Amortization of internal use software	36	45	42
Interest capitalized during development and construction	$ 84	$ 88	$ 155