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&lt;p style="margin-top: 18px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;8. Capital Stock &lt;/b&gt;&lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 6px; margin-bottom: 0px; margin-left: 2%;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;&lt;i&gt;Issuance of Common Stock &lt;/i&gt;&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 6px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;On January&amp;nbsp;5, 2011, the Company completed a secondary public offering of 11,500,000 shares of its common stock, including 1,500,000 shares pursuant to the underwriters' overallotment option, at a price to the public of $28.75 per share, and received net proceeds of approximately $325,707 after the payment of underwriting discounts and expenses. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 12px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;On March&amp;nbsp;18, 2011, the Company completed a secondary public offering of 14,500,000 shares of its common stock at a price to the public of $28.50 per share, and received net proceeds of approximately $407,606 after the payment of underwriting discounts and expenses. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 18px; margin-bottom: 0px; margin-left: 2%;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;&lt;i&gt;Issuance of Common Stock &amp;ndash; CEO Program &lt;/i&gt;&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 6px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;On October&amp;nbsp;9, 2009, the Company entered into a Sales Agreement (the "Sales Agreement") with Cantor Fitzgerald&amp;nbsp;&amp;amp; Co. ("Cantor") to create a controlled equity offering program (the "CEO Program"). Under the terms of the Sales Agreement, the Company may offer and sell up to 5,000,000 shares of its common stock from time to time through Cantor, acting as agent and/or principal. Sales of the shares of common stock, if any, may be made in private transactions, negotiated transactions or any method permitted by law deemed to an "at the market" offering as defined in Rule 415 under the Securities Act of 1933, as amended, including sales made directly on the New York Stock Exchange ("NYSE") or to or through a market maker other than on an exchange. For the three months ended March&amp;nbsp;31, 2011, the Company issued 450,000 shares of common stock in at-the-market transactions, raising net proceeds to the Company, after sales commissions and fees, of $13,404. In addition to sales commission, the Company incurs legal, accounting and other fees associated with the issuance of shares under this program. The total amount charged to additional paid in capital in connection with the issuance of these shares was $235 for the three months ended March&amp;nbsp;31, 2011. The shares of common stock issuable pursuant to the CEO Program are registered with the SEC on the Company's Registration Statement on Form S-3 (No. 333-159145), which became effective upon filing on October&amp;nbsp;9, 2009. &lt;/font&gt;&lt;/p&gt; &lt;/div&gt;</NonNumbericText><NonNumericTextHeader>8. Capital Stock

Issuance of Common Stock

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 -Publisher SEC
 -Name Regulation S-X (SX)
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 -Paragraph 29
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
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 -Paragraph 30
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
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