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Summary of  Significant Accounting Policies&lt;/font&gt;&lt;/strong&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/font&gt; &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;For  more information regarding our significant accounting policies and  estimates, please refer to &amp;#8220;Summary of Significant Accounting  Policies&amp;#8221; contained in our Annual Report on Form 10-K for the  year ended December&amp;#160;31, 2012.&lt;/font&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;strong&gt;&lt;em&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/font&gt;&lt;/em&gt;&lt;/strong&gt; &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;strong&gt;&lt;em&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;Principles of  Consolidation and Basis of Presentation&lt;/font&gt;&lt;/em&gt;&lt;/strong&gt;&lt;font  style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/font&gt; &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;The  accompanying condensed consolidated financial statements include  the accounts of the Company and its wholly-owned subsidiaries. All  significant intercompany balances and transactions have been  eliminated in consolidation. In accordance with the guidance for  the consolidation of variable interest entities  (&amp;#8220;VIEs&amp;#8221;), we analyze our variable interests, including  investments in partnerships and joint ventures, to determine if the  entity in which we have a variable interest is a variable interest  entity. Our analysis includes both quantitative and qualitative  reviews, based on our review of the design of the entity, its  organizational structure including decision-making ability, risk  and reward sharing experience and financial condition of other  partner(s), voting rights, involvement in day-to-day capital and  operating decisions and financial agreements. We also use  quantitative and qualitative analyses to determine if we must  consolidate a variable interest entity as the primary  beneficiary.&lt;/font&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;strong&gt;&lt;em&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/font&gt;&lt;/em&gt;&lt;/strong&gt; &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;strong&gt;&lt;em&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;Interim Financial  Information&lt;/font&gt;&lt;/em&gt;&lt;/strong&gt;&lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt"&gt;  &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  &amp;#160;&lt;/font&gt; &lt;font style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 12pt"&gt;&lt;/font&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0in 0in 0pt; FONT-SIZE: 10pt"&gt;  &lt;font style="LINE-HEIGHT: 115%; FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10pt"&gt;  The accompanying interim condensed consolidated financial  statements have been prepared by our management in accordance with  accounting principles generally accepted in the United States of  America (&amp;#8220;GAAP&amp;#8221;) and in conjunction with the rules and  regulations of the SEC. Certain information and note disclosures  required for annual financial statements have been condensed or  excluded pursuant to SEC rules and regulations. Accordingly, the  interim condensed consolidated financial statements do not include  all of the information and notes required by GAAP for complete  financial statements. The accompanying financial information  reflects all adjustments which are, in the opinion of our  management, of a normal recurring nature and necessary for a fair  presentation of our financial position, results of operations and  cash flows for the interim periods. Operating results for the three  and six months ended June 30, 2013 are not necessarily indicative  of the results that may be expected for the year ending  December&amp;#160;31, 2013. Our accompanying interim condensed  consolidated financial statements should be read in conjunction  with our audited condensed consolidated financial statements and  the notes thereto included on our 2012 Annual Report on Form 10-K,  as filed with the SEC.&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 all significant accounting policies of the reporting entity.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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