Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Original cost	$ 115,869		$ 116,469
Less accumulated depreciation and amortization	(48,126)		(47,642)
Property, plant and equipment - net	67,743		68,827
Depreciation and amortization	$ 2,275	$ 2,309