2.2.0.25falsefalse10200 - Disclosure - Summary of Significant Accounting Policiestruefalsefalse1falsefalseUSDfalsefalse1/1/2011 - 3/31/2011
USD ($)
USD ($) / shares
$FROM_Jan01_2011_TO_Mar31_2011http://www.sec.gov/CIK0000073020duration2011-01-01T00:00:002011-03-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDpershareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0nwn_DisclosureSummaryOfSignificantAccountingPoliciesnwnfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalse3false0us-gaap_SignificantAccountingPoliciesTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;margin-left:0px;">2</font><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;">.</font><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;">       </font><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;text-decoration:underline;">S</font><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;text-decoration:underline;">ummary of Significant Accounting Policies</font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;font-style:italic;text-decoration:underline;margin-left:0px;">Industry Regulation</font></p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;margin-left:0px;"> </font></p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;margin-left:36px;">At </font><font style="font-family:Times New Roman;font-size:11pt;">March 31, 2011 </font><font style="font-family:Times New Roman;font-size:11pt;">and</font><font style="font-family:Times New Roman;font-size:11pt;"> 2010</font><font style="font-family:Times New Roman;font-size:11pt;"> and at December 31, </font><font style="font-family:Times New Roman;font-size:11pt;">2010</font><font style="font-family:Times New Roman;font-size:11pt;">, the amounts deferred as regulatory assets and liabilities were as follows:</font></p><p style='margin-top: 0pt; margin-bottom: 0pt;'></p><div><table style="border-collapse:collapse;margin-top:20px;"><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"> <sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td colspan="7" style="width: 340px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:340px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">Regulatory Assets</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"> <sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">March 31,</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">March 31,</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">December 31,</font></td></tr><tr style="height: 20px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="TEXT-DECORATION: underline;FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Thousands</font><sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2011</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2010</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2010</font></td></tr><tr style="height: 20px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Current:</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Unrealized loss on derivatives</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 25,655</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 39,365</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 38,437</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Pension and other postretirement benefit liabilities</font><sup>(2)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 10,988</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 7,502</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 10,988</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Other</font><sup>(3)</sup></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 11,552</font></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 9,005</font></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 3,289</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Total current</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 48,195</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 55,872</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 52,714</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Non-current:</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Unrealized loss on derivatives</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 13,914</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 18,637</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 17,022</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Income tax asset</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 70,241</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 75,515</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 72,341</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Pension and other postretirement benefit liabilities</font><sup>(2)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 115,490</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 108,010</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 118,248</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Environmental costs</font><sup>(4)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 117,544</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 107,537</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 114,311</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Other</font><sup>(3)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 28,263</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 22,263</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 26,975</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Total non-current</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 345,452</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 331,962</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 348,897</font></td></tr><tr style="height: 21px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"> <sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"> <sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td colspan="7" style="width: 340px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:340px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">Regulatory Liabilities</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"> <sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">March 31,</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">March 31,</font></td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: center;">December 31,</font></td></tr><tr style="height: 20px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="TEXT-DECORATION: underline;FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Thousands</font><sup></sup></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2011</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2010</font></td><td style="width: 10px; text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:center;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #00b050;TEXT-ALIGN: center;">2010</font></td></tr><tr style="height: 20px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Current:</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:solid;border-top-width:1px;text-align:left;border-color:#000000;min-width:100px;"> </td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Gas costs payable</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 14,144</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 26,164</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 15,583</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Unrealized gain on derivatives</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 4,861</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 450</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,245</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Other</font><sup>(3)</sup></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 10,011</font></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 9,418</font></td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> -</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Total current</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 29,016</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 36,032</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 17,828</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Non-current:</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:double;border-top-width:3px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-top-style:double;border-top-width:3px;text-align:left;border-color:#000000;min-width:100px;"> </td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Gas costs payable</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 3,932</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,377</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,297</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Unrealized gain on derivatives</font><sup>(1)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 1,560</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 5</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 628</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Accrued asset removal costs</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 256,203</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 242,952</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 252,941</font></td></tr><tr style="height: 20px"><td style="width: 15px; text-align:left;border-color:#000000;min-width:15px;"> </td><td style="width: 345px; text-align:left;border-color:#000000;min-width:345px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Other</font><sup>(3)</sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,181</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,183</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:10px;"> </td><td style="width: 100px; border-bottom-style:solid;border-bottom-width:1px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 2,165</font></td></tr><tr style="height: 21px"><td colspan="2" style="width: 360px; text-align:left;border-color:#000000;min-width:360px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: left;">Total non-current</font><sup></sup></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 263,876</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 247,517</font></td><td style="width: 10px; text-align:left;border-color:#000000;min-width:10px;"> </td><td style="width: 10px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:10px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;">$</font></td><td style="width: 100px; border-top-style:solid;border-top-width:1px;border-bottom-style:double;border-bottom-width:3px;text-align:right;border-color:#000000;min-width:100px;"><font style="FONT-FAMILY: Times New Roman;FONT-SIZE: 11pt;COLOR: #000000;TEXT-ALIGN: right;"> 258,031</font></td></tr></table></div><p style='margin-top: 0pt; margin-bottom: 0pt;'></p><p style='margin-top:12pt; margin-bottom:0pt'></p><ul><li style="margin-left:36px;list-style:decimal;"><font style="font-family:Times New Roman;font-size:11pt;">An unreal</font><font style="font-family:Times New Roman;font-size:11pt;">ized gain or loss on</font><font style="font-family:Times New Roman;font-size:11pt;"> derivatives does not earn a rate of return or a carrying charge.  These amounts, when realized at settlement, are recoverable through utility rates as part of the </font><font style="font-family:Times New Roman;font-size:11pt;">Purchased Gas Adjustment</font><font style="font-family:Times New Roman;font-size:11pt;"> mechanism.</font></li><li style="margin-left:36px;list-style:decimal;"><font style="font-family:Times New Roman;font-size:11pt;">Certain pension</font><font style="font-family:Times New Roman;font-size:11pt;"> and other postretirement benefit </font><font style="font-family:Times New Roman;font-size:11pt;">liabilities</font><font style="font-family:Times New Roman;font-size:11pt;"> </font><font style="font-family:Times New Roman;font-size:11pt;">o</font><font style="font-family:Times New Roman;font-size:11pt;">f the utility </font><font style="font-family:Times New Roman;font-size:11pt;">are approved for regulatory deferral.  Such amounts are recoverable in rates, including an interest component, when recognized in </font><font style="font-family:Times New Roman;font-size:11pt;">pension expense or net periodic benefit cost</font><font style="font-family:Times New Roman;font-size:11pt;"> (see </font><font style="font-family:Times New Roman;font-size:11pt;">Note </font><font style="font-family:Times New Roman;font-size:11pt;">9</font><font style="font-family:Times New Roman;font-size:11pt;">).</font></li><li style="margin-left:36px;list-style:decimal;"><font style="font-family:Times New Roman;font-size:11pt;">Other primarily consists of deferrals and amortizations under other approved regulatory mechanisms.  The accounts being amortized typically earn a rate of return or carrying charge.</font></li><li style="margin-left:36px;list-style:decimal;"><font style="font-family:Times New Roman;font-size:11pt;">Environ</font><font style="font-family:Times New Roman;font-size:11pt;">mental costs are related to certain</font><font style="font-family:Times New Roman;font-size:11pt;"> </font><font style="font-family:Times New Roman;font-size:11pt;">utility </font><font style="font-family:Times New Roman;font-size:11pt;">sites that are approved for regulatory </font><font style="font-family:Times New Roman;font-size:11pt;">deferral.  We earn the </font><font style="font-family:Times New Roman;font-size:11pt;">utility's </font><font style="font-family:Times New Roman;font-size:11pt;">authorized rate of return as a carrying charge on amounts paid, whereas the amounts accrued but not yet paid do not earn a rate of return or a carrying charge until expended.</font></li></ul><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;font-style:italic;text-decoration:underline;margin-left:0px;">Revenue Recognition</font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:12pt;margin-left:36px;">Utility and non-utility revenues, which are derived primarily from the sale, transportation or storage of natural gas, are recognized upon the delivery of gas commodity or service to customers. Since 2007, utility revenues have also included the recognition of a regulatory adjustment for income taxes paid pursuant to a legislative rule (commonly referred to as SB 408) in effect for certain gas and electric utilities in Oregon. Under SB 408, we are required to automatically implement a rate refund, or a rate surcharge, to utility customers on an annual basis. The refund or surcharge amount is based on the estimated difference between income taxes paid and income taxes authorized to be collected in customer rates. We have recorded the estimated refund, or surcharge, each quarter since 2007 based on the estimated annual amount to be recognized. However, on March 29, 2011, a legislative bill was introduced that would repeal SB 408 if enacted as drafted in its current form (SB 967 or Bill). As of May 4, 2011, the Oregon Senate had approved SB 967, but the Bill has not been approved by the Oregon House of Representatives or signed by the Governor of Oregon. We currently believe there is substantial uncertainty surrounding the continuation of the current legal requirements of SB 408. Accordingly, we determined that the threshold for recognizing revenues under the accounting standard for the effects of regulation had not been met, and therefore we did not record an estimated refund, or surcharge, in the first quarter of 2011 for this regulatory adjustment for income taxes paid. </font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;font-style:italic;text-decoration:underline;margin-left:0px;">New Accounting </font><font style="font-family:Times New Roman;font-size:11pt;font-style:italic;text-decoration:underline;">Standards</font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;text-decoration:underline;margin-left:36px;">Adopted Standards</font></p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;margin-left:0px;"> </font></p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;margin-left:36px;">Fair Value Disclosures.</font><font style="font-family:Times New Roman;font-size:11pt;font-weight:bold;"> </font><font style="font-family:Times New Roman;font-size:11pt;">In January </font><font style="font-family:Times New Roman;font-size:11pt;">2010</font><font style="font-family:Times New Roman;font-size:11pt;">, the Financial Accounting Standards Board issued </font><font style="font-family:Times New Roman;font-size:11pt;">authoritative guidance</font><font style="font-family:Times New Roman;font-size:11pt;"> on new fair value measurements and disclosures.  This guidance requires additional disclosures for fair value measurements that use significant assumptions not observable in active markets (i.e. level 3 valuations)</font><font style="font-family:Times New Roman;font-size:11pt;">,</font><font style="font-family:Times New Roman;font-size:11pt;"> including a rollforw</font><font style="font-family:Times New Roman;font-size:11pt;">ard schedule. These changes were</font><font style="font-family:Times New Roman;font-size:11pt;"> effective for periods beginning after December 15, 2010; however, we elected to early adopt these disclosure requirements, as shown in Note</font><font style="font-family:Times New Roman;font-size:11pt;"> 9 in our 2010 Form 10-K.</font><font style="font-family:Times New Roman;font-size:11pt;"> The adoption of this standard did not have</font><font style="font-family:Times New Roman;font-size:11pt;"> a material effect on our financial statement disclosures.</font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;text-decoration:underline;margin-left:36px;">Recent Accounting Pronouncements</font></p><p style='margin-top:0pt; margin-bottom:0pt'> </p><p style='margin-top:0pt; margin-bottom:0pt'><font style="font-family:Times New Roman;font-size:11pt;margin-left:36px;">There have been no r</font><font style="font-family:Times New Roman;font-size:11pt;">ecent accounting pronouncements issued, but not yet effective, which are expected to have a material impact on our financial condition, results of operations or cash flows.</font></p>2.       Summary of Significant Accounting Policies Industry Regulation At March 31, 2011 and 2010 and at December 31,falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis element may be used to describe all significant accounting policies of the reporting entity.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 22
-Paragraph 8
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