Short-Term Investments and Available-For-Sale Securities	9 Months Ended
Sep. 30, 2011
Short-Term Investments and Available-For-Sale Securities
Short-Term Investments and Available-For-Sale Securities	2. Short-Term Investments and Available-For-Sale Securities As of September 30, 2011, short-term investments included investments with original maturities of three months or more of $4.7 million and available-for-sale securities of less than $0.1 million. As of December 31, 2010, short-term investments included investments with original maturities of three months or more of $46.2 million and available-for-sale securities of $0.2 million.

This item represents the entire disclosure related to Investments in Certain Debt and Equity Securities (and certain other trading assets) which include all debt and equity securities (other than those equity securities accounted for under the equity or cost methods of accounting) with readily determinable fair values. Other trading assets include assets that are carried on the balance sheet at fair value and held for trading purposes. A debt security represents a creditor relationship with an enterprise that is in the form of a security. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities (and other trading assets).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 3, 19, 20, 21, 22, 137

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