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In&amp;#160;2011, the Company completed an initial public offering of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;28,750,000&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; shares, inclusive of the exercise of the over-allotment option exercised in July 2011, of its common stock at &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$18.00&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; per share, prior to underwriting discounts, commissions and other related offering expenses of approximately &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$33.8 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:13px;text-align:left;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;"&gt;Common Stock of Vanguard and Corporate Reorganization&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:13px;text-align:left;text-indent:32px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;In connection with the Blackstone merger in 2004, Blackstone, Morgan Stanley Capital Partners and its affiliates, members of management and other investors acquired the membership units of VHS Holdings, LLC ("Holdings").  Holdings then acquired the common stock of the Company, in addition Blackstone invested &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$125.0 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; directly in the common stock of the Company.  In February&amp;#160;2005, other investors purchased additional membership units of Holdings, which Holdings then invested in the common stock of the Company.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-top:13px;text-align:left;text-indent:32px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Immediately prior to the Company&amp;#8217;s initial public offering, Holdings was merged with and into the Company so that the Company survived the merger (the &amp;#8220;Holdings Merger&amp;#8221;).  As a result of the Holdings Merger, the holders of the outstanding units of Holdings received the same financial values of ownership interests from the equity issued by the Company as that surrendered in Holdings calculated based on the deemed equity value of the Company from the initial public offering. The net impact from the Holdings Merger resulted in the Company issuing to the former unit holders in Holdings an additional &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;1,720,379&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; shares of common stock, an additional &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;1,684,733&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; shares of restricted stock but with full voting rights and an additional &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;1,245,086&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; options to purchase common stock. The restricted stock issued in the Holdings Merger vested in September&amp;#160;2012.&lt;/font&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable).  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