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USD ($)

USD ($) / shares
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       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;8.&amp;#160;&amp;#160;&lt;/font&gt;&lt;/b&gt;
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       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Stockholders&amp;#8217;
       Equity&lt;/font&gt;&lt;/b&gt;
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       Stock&lt;/font&gt;&lt;/i&gt;
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   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
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   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #0c1c47; background: transparent"&gt;
       The Company has 5,000,000&amp;#160;shares of preferred stock
       (Preferred Stock) authorized, none of which are issued.
   &lt;/div&gt;
   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
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       &lt;i&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Common
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   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
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       Common stockholders are entitled to one vote per share and
       dividends when declared by the Company&amp;#8217;s Board of
       Directors, subject to the preferential rights of any outstanding
       shares of Preferred Stock.
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       Employees and directors of the Company purchased
       557,725&amp;#160;shares, 231,022&amp;#160;shares, and
       320,638&amp;#160;shares of common stock during the years ended
       December&amp;#160;31, 2010, 2009 and 2008, respectively, pursuant to
       option exercises and the Company&amp;#8217;s employee stock purchase
       plan. The aggregate net proceeds to the Company resulting from
       these purchases were approximately $3.4&amp;#160;million,
       $1.8&amp;#160;million, and $5.5&amp;#160;million during the years ended
       December&amp;#160;31, 2010, 2009 and 2008, respectively, and are
       included within the financing activities section of the
       consolidated statements of cash flows. The Company issued
       76,044&amp;#160;shares, 319,348&amp;#160;shares and 92,970&amp;#160;shares
       under restricted stock awards during the years ended
       December&amp;#160;31, 2010, 2009 and 2008, respectively.
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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 5
 -Paragraph 15

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 04
 -Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 08
 -Paragraph d
 -Article 4

Reference 4: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 4
 -Section C, E

Reference 5: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Accounting Principles Board Opinion (APB)
 -Number 12
 -Paragraph 10

Reference 6: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 02
 -Paragraph 29, 30, 31
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 129
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 08
 -Article 4

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