2.2.0.25falsefalse1070 - Disclosure - Fair Valuetruefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $D2010http://www.sec.gov/CIK0001166036duration2010-01-01T00:00:002010-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0mwe_FairValueDisclosureAbstractmwefalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair Value3false0us-gaap_FairValueDisclosuresTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<table style="font-size:10pt; font-family:'Times New Roman',times,serif;"> <tr> <td> 7. Fair Value Fair Value Measurement         Fair value measurements and disclosures relate primarily to the Partnership's derivative positions discussed in Note 6. See Note 2 for a description of the guidance and the fair value hierarchy.         The derivative contracts are measured at fair value on a recurring basis and classified within Level 2 and Level 3 of the valuation hierarchy. The Level 2 and Level 3 measurements are obtained using a market approach. LIBOR rates are an observable input for the measurement of all derivative contracts. The measurements for all commodity contracts contain observable inputs in the form of forward prices based on WTI crude oil prices; Columbia Appalachia, Henry Hub and Houston Ship Channel natural gas prices; Mont Belvieu and Conway NGL prices; and ERCOT electricity prices. Level 2 instruments include crude oil and natural gas swap contracts; the valuations are based on the appropriate commodity prices and contain no significant unobservable inputs. Level 3 instruments include crude oil options, all NGL transactions, embedded derivatives in commodity contracts and the embedded put options. The significant unobservable inputs for crude oil options, NGL transactions and embedded derivatives in commodity contracts include option volatilities and commodity prices interpolated and extrapolated due to inactive markets. The significant unobservable inputs for the embedded put options are option volatilities and management's assumptions about the probability of specific events occurring in the future.         The following table presents the financial instruments carried at fair value as of December 31, 2010 and 2009, and by the valuation hierarchy (as described above, in thousands): <div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 20%; WIDTH: 60%; PADDING-TOP: 0pt; POSITION: relative">   <div align="center"> <table cellspacing="0" cellpadding="0" width="100%" border="0"> <tr style="HEIGHT: 0px"> <td style="FONT-FAMILY: times" align="left" width="10"></td> <td style="FONT-FAMILY: times" align="left"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="39"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="56"></td> <td style="FONT-FAMILY: times" width="12"></td></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" nowrap="nowrap" align="left" colspan="2"> <div style="MARGIN-BOTTOM: 0pt; WIDTH: 85pt; BORDER-BOTTOM: #000000 1pt solid">As of December 31, 2010 </div></th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Assets </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Liabilities </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Significant other observable inputs (Level 2)</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Commodity contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">52</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(77,776</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Significant unobservable inputs (Level 3)</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Commodity contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">3,674</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(18,031</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Embedded derivatives in commodity contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">1,036</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(35,972</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Total carrying value in Consolidated Balance Sheet</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">4,762</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(131,779</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr></table></div> </div>   <div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 20%; WIDTH: 60%; PADDING-TOP: 0pt; POSITION: relative">   <div align="center"> <table cellspacing="0" cellpadding="0" width="100%" border="0"> <tr style="HEIGHT: 0px"> <td style="FONT-FAMILY: times" align="left" width="10"></td> <td style="FONT-FAMILY: times" align="left"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="45"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="56"></td> <td style="FONT-FAMILY: times" width="12"></td></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" nowrap="nowrap" align="left" colspan="2"> <div style="MARGIN-BOTTOM: 0pt; WIDTH: 85pt; BORDER-BOTTOM: #000000 1pt solid">As of December 31, 2009 </div></th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Assets </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Liabilities </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Significant other observable inputs (Level 2)</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Commodity derivative contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">9,920</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(63,242</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Significant unobservable inputs (Level 3)</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Commodity derivative contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">14,202</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(25,542</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Embedded derivatives in commodity contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right"></td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(34,199</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Interest rate contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">509</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right"></td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" valign="bottom"> Embedded derivative in debt contracts</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right"></td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(190</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="white"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> Total carrying value in Consolidated Balance Sheet</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">24,631</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">(123,173</td> <td style="FONT-FAMILY: times" valign="bottom">)</td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr></table></div> </div> Changes in Level 3 Fair Value Measurements         The tables below include a rollforward of the balance sheet amounts for the year ended December 31, 2010 and 2009 (including the change in fair value) for assets and liabilities classified by the Partnership within Level 3 of the valuation hierarchy (in thousands). <div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 10%; WIDTH: 73%; PADDING-TOP: 0pt; POSITION: relative">   <div align="center"> <table cellspacing="0" cellpadding="0" width="110%" border="0"> <tr style="HEIGHT: 0px"> <td style="FONT-FAMILY: times" align="left"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="72"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="72"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="61"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="86"></td> <td style="FONT-FAMILY: times" width="12"></td></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" align="left">  </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="11">Year Ended December 31, 2010 </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" align="left">  </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Commodity Derivative Contracts (net)</th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Embedded Derivatives in Commodity Contracts (net) </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Interest Rate Contracts </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Embedded Derivative in Debt Contract</th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> Fair value at beginning of period</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(11,340</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(34,199</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">509</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(190</td> <td style="FONT-FAMILY: times">)</td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"> <td style="FONT-FAMILY: times"> Total gain or loss (realized and unrealized) included in earnings(1)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(11,093</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(11,792</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">1,871</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">190</td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> Purchases, sales, issuances and settlements (net)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">8,076</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">11,055</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(2,380</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"> <td style="FONT-FAMILY: times"> Fair Value at End of Period</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(14,357</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(34,936</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> The amount of total gains or losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at December 31(1)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(13,101</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(9,329</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr></table></div> </div>   <div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 10%; WIDTH: 62%; PADDING-TOP: 0pt; POSITION: relative">   <div align="center"> <table cellspacing="0" cellpadding="0" width="130%" border="0"> <tr style="HEIGHT: 0px"> <td style="FONT-FAMILY: times" align="left"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="72"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="72"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="61"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="67"></td> <td style="FONT-FAMILY: times" width="12"></td> <td style="FONT-FAMILY: times" align="right" width="7"></td> <td style="FONT-FAMILY: times" width="47"></td> <td style="FONT-FAMILY: times" width="12"></td></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" align="left">  </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="14">Year Ended December 31, 2009 </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="bottom"> <th style="FONT-FAMILY: times" align="left">  </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Commodity Derivative Contracts (net)</th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Embedded Derivatives in Commodity Contracts (net) </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Interest Rate Contracts </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Embedded Derivative in Debt Contract</th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Trading Securities </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> Fair value at beginning of period</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">72,478</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(22</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">512</td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"> <td style="FONT-FAMILY: times"> Total gain or loss (realized and unrealized) included in earnings(1)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(51,833</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(39,549</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">2,509</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">336</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">40</td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> Purchases, sales, issuances and settlements (net)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(31,985</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">5,372</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(2,000</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(526</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">(552</td> <td style="FONT-FAMILY: times">)</td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"> <td style="FONT-FAMILY: times"> Fair Value at End of Period</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(11,340</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(34,199</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">509</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(190</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times"> The amount of total gains or losses for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at December 31(1)</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(35,616</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">(34,177</td> <td style="FONT-FAMILY: times">)</td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">509</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right">336</td> <td style="FONT-FAMILY: times"> </td> <td style="FONT-FAMILY: times" align="right">$</td> <td style="FONT-FAMILY: times" align="right"></td> <td style="FONT-FAMILY: times"> </td></tr> <tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr></table></div> </div> <div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 10%; PADDING-TOP: 0pt; POSITION: relative; TEXT-ALIGN: left"> <hr style="COLOR: #000000" align="left" width="26%" noshade="noshade" size="1" /> <dl compact="compact"> <dt style="MARGIN-BOTTOM: -11pt; FONT-FAMILY: times">(1)</dt> <dd style="FONT-FAMILY: times">Gains and losses on Commodity Derivative Contracts classified as Level 3 are recorded in Derivative (loss) gain related to revenue. Gains and losses on Embedded Derivatives in Commodity Contracts are recorded in Purchased product costs, Derivative loss related to purchased product costs and Derivative (gain) loss related to facility expenses. Gains on Embedded Derivative in Debt Contract are recorded in Miscellaneous income (expense), net. Gains and losses on Interest Rate Contracts are recorded in Derivative gain related to interest expense. </dd></dl></div> Assets and liabilities measured at fair value on a nonrecurring basis         Certain assets and liabilities are measured at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances. As of June 30, 2009, certain long-lived assets of Wirth Gathering, a consolidated subsidiary, were required to be measured at fair value in conjunction with the Partnership's impairment evaluation for long-lived assets. Property, plant and equipment and intangible assets with a net book value of $5.2 million and $0.7 million, respectively, were written down to an estimated fair value of zero, resulting in an impairment charge of $5.9 million. The Partnership estimated the fair value of these assets based on an income approach using significant unobservable inputs (Level 3). See Note 13 for further discussion of the impairment. As of December 31, 2010, there were no other assets or liabilities to be measured at fair value on a nonrecurring basis.</td></tr></table> 7. Fair Value Fair Value Measurement         Fair value measurements and disclosures relate primarily to thefalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis item represents the complete disclosure regarding the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the Company is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risk is are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15B -Subparagraph a, b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 3, 10, 14, 15 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44A, 44B Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32, 33, 34 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15C, 15D Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A -Subparagraph a-d Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 17-22, 27, 28 falsefalseFair Value12Fair ValueUnKnownUnKnownUnKnownUnKnownfalsetrue