Cash, Cash Equivalents and Marketable Securities (Details Textuals) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2011
Cash, Cash Equivalents and Marketable Securities (Textuals) [Abstract]
Cash, cash equivalents, and short-term investments held by our foreign subsidiaries	$ 1,780
Number of investments in unrealized loss position	100
Period for unrealized loss position	less than 12 months
Gross unrealized loss due to changes in interest rates	less than one million dollars