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Unrecognized tax benefits increased &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$0.3 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; during the &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;six months ended June 30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, and the increase, if recognized, would affect the effective tax rate.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-indent:18px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#160;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-indent:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company records deferred tax liabilities relating to property, plant, equipment and intangible assets primarily related to the Company&amp;#8217;s share of the book basis in excess of tax basis for the assets inside of the Partnership. The Company also records deferred taxes relating to the difference between the Company&amp;#8217;s book and tax basis of its investment in the Partnership. As of December&amp;#160;31, 2012, the difference between the Company&amp;#8217;s book and tax basis in its investment in the Partnership was a deferred tax asset of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$6.0 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; which was offset by a valuation allowance of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;$6.0 million&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;. 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