2.2.0.25falsefalse1080 - Disclosure - Significant Customers and Concentration of Credit Risktruefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 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_SignificantCustomersAndConcentrationOfCreditRiskDisclosureAbstractmwefalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseSignificant Customers and Concentration of Credit Risk3false0us-gaap_ConcentrationRiskDisclosureTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<table style="font-size:10pt; font-family:'Times New Roman',times,serif;"> <tr> <td> 8. Significant Customers and Concentration of Credit Risk         For the years ended December 31, 2010, 2009 and 2008, revenues from one customer totaled $198.6 million, $134.8 million and $234.0 million, representing 16.0%, 15.7% and 22.1% of Revenue, respectively. Sales to this customer are made primarily from the Southwest segment. As of December 31, 2010 and 2009, the Partnership had $5.1 million and $5.2 million of accounts receivable from this customer, respectively. </td></tr></table> 8. Significant Customers and Concentration of Credit Risk         For the years ended December 31, 2010, 2009 andfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescription of any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. The entity should inform financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date. Disclosure of any financial instrument credit risk concentration also should indicate the maximum amount of loss that would be incurred upon complete failure of the counterparty to perform and the entity's collateral policies or other policies that limit the loss exposure. This element may be used as a single block of text to encapsulate the entire disclosure including data and tables.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 21, 22, 24 falsefalseSignificant Customers and Concentration of Credit Risk12Significant Customers and Concentration of Credit RiskUnKnownUnKnownUnKnownUnKnownfalsetrue