Fair Value Measurements and Financial Instruments (Details 5) (Bonds Issued By Venezuelan Government [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2010
Bonds Issued By Venezuelan Government [Member]
Venezuelan Investments [Roll Forward]
Beginning balance	$ 642		$ 236
Unrealized gain (loss) on investment	(128)	22
Purchases and sales during the period	97	134
Ending balance	$ 611	$ 392	$ 236