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USD ($)

USD ($) / shares

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margin-bottom:0pt'&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0px;"&gt;Note&amp;#160;3&amp;#160;&amp;#8212; Intangible Assets&lt;/font&gt;&lt;/p&gt;&lt;p style='margin-top:0pt; margin-bottom:0pt'&gt;&amp;#160;&lt;/p&gt;&lt;p style='margin-top:0pt; margin-bottom:0pt'&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;margin-left:36px;"&gt;Our intangible assets consist of rights-of-way, easements, contracts and acquired customer relationships.  &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;Intangible assets consisted&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; of the following:&lt;/font&gt;&lt;/p&gt;&lt;p style='margin-top: 0pt; margin-bottom: 0pt;'&gt;&lt;/p&gt;&lt;div&gt;&lt;table style="border-collapse:collapse;margin-top:20px;"&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 410px; text-align:left;border-color:#000000;min-width:410px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="3"  style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"&gt;&lt;font style="FONT-WEIGHT: bold;FONT-FAMILY: Times New Roman;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: center;"&gt;March&amp;#160;31,&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="3"  style="width: 80px; text-align:center;border-color:#000000;min-width:80px;"&gt;&lt;font style="FONT-WEIGHT: bold;FONT-FAMILY: Times New Roman;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: center;"&gt;December&amp;#160;31,&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:center;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 410px; text-align:left;border-color:#000000;min-width:410px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="3"  style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"&gt;&lt;font style="FONT-WEIGHT: bold;FONT-FAMILY: Times New Roman;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: center;"&gt;2011&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="3"  style="width: 80px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:80px;"&gt;&lt;font style="FONT-WEIGHT: bold;FONT-FAMILY: Times New Roman;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: center;"&gt;2010&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:center;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 2px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 410px; text-align:left;border-color:#000000;min-width:410px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:60px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 24px; text-align:center;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 410px; text-align:left;border-color:#000000;min-width:410px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="7"  style="width: 170px; text-align:center;border-color:#000000;min-width:170px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 8pt;COLOR: #000000;TEXT-ALIGN: center;"&gt;(In thousands)&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:center;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="2"  style="width: 420px; text-align:left;border-color:#000000;min-width:420px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Rights-of-way and easements, at cost &lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; 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125,496&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="2"  style="width: 420px; text-align:left;border-color:#000000;min-width:420px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Less accumulated amortization for rights-of-way and easements &lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; (24,598)&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; (23,234)&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="2"  style="width: 420px; text-align:left;border-color:#000000;min-width:420px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Contracts &lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 107,916&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 107,916&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="2"  style="width: 420px; text-align:left;border-color:#000000;min-width:420px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Less accumulated amortization for contracts &lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 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text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 4,864&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 4,864&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td colspan="2"  style="width: 420px; text-align:left;border-color:#000000;min-width:420px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Less accumulated amortization for customer relationships &lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; (1,382)&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 60px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; (1,304)&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr style="height: 17px"&gt;&lt;td   style="width: 48px; text-align:left;border-color:#000000;min-width:48px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 410px; text-align:left;border-color:#000000;min-width:410px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;Intangible assets, net&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:left;border-color:#000000;min-width:10px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 60px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 186,994&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"&gt;&amp;#160;&lt;/td&gt;&lt;td   style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:left;border-color:#000000;min-width:10px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: left;"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 60px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:60px;"&gt;&lt;font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 10pt;COLOR: #000000;TEXT-ALIGN: right;"&gt; 188,585&lt;/font&gt;&lt;/td&gt;&lt;td   style="width: 24px; text-align:left;border-color:#000000;min-width:24px;"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;p style='margin-top: 0pt; margin-bottom: 0pt;'&gt;&lt;/p&gt;&lt;p style='margin-top:12pt; margin-bottom:0pt'&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;margin-left:36px;"&gt;During &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;the &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;three months ended &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;March&amp;#160;31, 2011&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;and&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;20&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;10&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;,&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; we did not &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;place in service &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;any &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;intangible assets&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; with future renewals or extension costs.  &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;As of &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;March&amp;#160;31, 2011&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2010&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;, the weighted average amortization period for all of our intangible assets was&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;19&lt;/font&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:10pt;"&gt;years and&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; 2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;0&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years, respectively.  The weighted average amortization period for our rights-of-way and easements, contracts and customer relationships wa&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;s &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;0&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years, &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;18&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;ye&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;ars, respectively, as of &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;March&amp;#160;31, 2011&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;.  The weighted average amortization period for our rights-of-way and easements, contracts and customer relationships was&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; 2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years, &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;8&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years and&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; 1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;&amp;#160;years, respectively, as of &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;March&amp;#160;31, 2010&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/p&gt;&lt;p style='margin-top:0pt; margin-bottom:0pt'&gt;&amp;#160;&lt;/p&gt;&lt;p style='margin-top:0pt; margin-bottom:0pt'&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;margin-left:36px;"&gt;Amortization expense was &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2,898,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; and&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; $&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2,780&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;,000 for the three months ended &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;March&amp;#160;31, 2011&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;2010&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;, respectively.&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;  &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;Estimated aggregate amortization expense remaining for 2011 and each of the five succeeding fiscal years is approximately: &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;8,706,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;2&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;11,68&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;4&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;3&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$11,&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;5&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;10&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;,000;&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;4&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;11,232,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;5&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;11,17&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;1&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;; and &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;201&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;6&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;font-style:italic;"&gt;&amp;#160;&amp;#8212; &lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;$&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;11,151,000&lt;/font&gt;&lt;font style="font-family:Times New Roman;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/p&gt;</NonNumbericText><NonNumericTextHeader>Note&amp;#160;3&amp;#160;&amp;#8212; Intangible Assets&amp;#160;Our intangible assets consist of rights-of-way, easements, contracts and acquired customer relationships. </NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>This block of text may be used to disclose all or part of the information related to intangible assets.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 142
 -Paragraph  44, 45, 46

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