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&lt;td&gt;During the three months ended September&amp;nbsp;30, 2010, we redeemed, at par, the remaining $0.8 million balance of our auction rate securities, which are variable rate bonds tied to short-term interest rates which reset through a Dutch auction at predetermined short intervals. As of December&amp;nbsp;31, 2009, we held $42.0&amp;nbsp;million at par value in auction rate securities that were issued by municipalities and state education agencies. The auction rate securities issued by state education agencies represented pools of student loans for which repayment is substantially guaranteed by the U.S. government under the Federal Family Education Loan Program. All of our investments in auction rate securities had at least a double A rating. As of December&amp;nbsp;31, 2009, the par value of our auction rate securities issued by municipalities and state education agencies was $12.0&amp;nbsp;million and $30.0&amp;nbsp;million, respectively.&lt;/td&gt;&lt;/tr&gt;
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&lt;td&gt;&lt;b&gt;Auction Rate Securities under Settlement Agreement &lt;/b&gt;&lt;i&gt;&amp;#8212; &lt;/i&gt;Due to continuing failures of auctions for our auction rate securities, we entered into an auction rate security rights agreement (the "Settlement") with UBS Financial Services, Inc. ("UBS") in November&amp;nbsp;2008 that permitted us to sell, or put, certain auction rate securities back to UBS at par value at any time during the period from June&amp;nbsp;30, 2010 through July&amp;nbsp;2, 2012. As of December&amp;nbsp;31, 2009, the par value of our auction rate securities covered under the Settlement was $30.8&amp;nbsp;million. These auction rate securities were classified as trading securities; consequently, we were required to assess the fair value of these auction rate securities and of the Settlement and to record changes in earnings each period until the Settlement was exercised and the securities were sold.&lt;/td&gt;&lt;/tr&gt;
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&lt;td&gt;As of December&amp;nbsp;31, 2009, the fair value of the auction rate securities covered under the Settlement was $28.5&amp;nbsp;million, a decline of $2.3&amp;nbsp;million from par value. However, as we would be permitted to put these securities back to UBS at par, the fair value assessment of the Settlement was measured at an offsetting $2.3&amp;nbsp;million. Because all auction rate securities covered under the Settlement were either sold or put to UBS during the nine months ended September&amp;nbsp;30, 2010, we reversed the other-than-temporary impairment of $2.3 million on the auction rate securities and the offsetting gain of $2.3&amp;nbsp;million on the fair value assessment of the Settlement. These changes were reflected in Other income (expense), net for the nine months ended September&amp;nbsp;30, 2010. As of September&amp;nbsp;30, 2009, the fair value of the auction rate securities covered under the Settlement was $28.0&amp;nbsp;million, a decline of $2.8&amp;nbsp;million from par value, but an improvement in the $3.1&amp;nbsp;million impairment recognized at December&amp;nbsp;31, 2008. For the three months and nine months ended September&amp;nbsp;30, 2009, we reversed $1.4&amp;nbsp;million and $0.3&amp;nbsp;million, respectively, of the other-than-temporary impairment on the auction rate securities. For the three months and nine months ended September&amp;nbsp;30, 2009, we also reversed $1.4&amp;nbsp;million and $0.3&amp;nbsp;million, respectively, of the gain on the fair value assessment of the Settlement. These changes were reflected in Other income (expense), net on the Condensed Consolidated Statement of Operations for the three and nine months ended September&amp;nbsp;30, 2009.&lt;/td&gt;&lt;/tr&gt;
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&lt;td&gt;&lt;b&gt;Auction Rate Securities Not Covered under Settlement &lt;/b&gt;&lt;i&gt;&amp;#8212; &lt;/i&gt;As of December&amp;nbsp;31, 2009, the par value of our auction rate securities not covered under the Settlement was $11.2&amp;nbsp;million. In March&amp;nbsp;2010, we sold $11.2&amp;nbsp;million of our auction rate securities not covered under the Settlement for $10.7&amp;nbsp;million. We recognized the $0.5&amp;nbsp;million loss on the sale of the securities in Other income (expense), net on the Condensed Consolidated Statement of Operations for the nine months ended September&amp;nbsp;30, 2010.&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText>
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Marketable Securities


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      <ElementReferences>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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