Fair Value Measurements and Financial Instruments (Details 5) (Bonds Issued By Venezuelan Government [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Bonds Issued By Venezuelan Government [Member]
Venezuelan Investments [Roll Forward]
Beginning balance	$ 399	$ 685
Unrealized gain (loss) on investment	(1)	(298)
Purchases and sales during the period	33	54
Ending balance	$ 431	$ 441