2.2.0.25falsefalse1180 - Disclosure - Equitytruefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 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_PartnersCapitalDisclosureAbstractmwefalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseEquity3false0us-gaap_PartnersCapitalNotesDisclosureTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<table style="font-size:10pt; font-family:'Times New Roman',times,serif;"> <tr> <td> 18. Equity         As described in Note 3, the Partnership acquired the Corporation through a merger of MWEP, L.L.C. with and into the Corporation, pursuant to which all remaining shares of the Corporation's common stock were converted into approximately 15.5 million Partnership common units. The Partnership Agreement stipulates the circumstances under which the Partnership is authorized to issue new capital, maintain capital accounts, and distribute cash.         The Partnership Agreement contains specific provisions for the allocation of net income and losses to each of the partners for purposes of maintaining their respective partner capital accounts. <ul> <li style="list-style: none"> Distributions of Available Cash</li></ul>         The Partnership distributes all of its Available Cash (as defined) to unitholders of record within 45 days after the end of each quarter. Available Cash is generally defined as all cash and cash equivalents of the Partnership on hand at the end of each quarter, less reserves established by the general partner for future requirements, plus all cash for the quarter from working capital borrowings made after the end of the quarter. The general partner has the discretion to establish cash reserves that are necessary or appropriate to (i) provide for the proper conduct of the Partnership's business; (ii) comply with applicable law, any debt instruments or other agreements; or (iii) provide funds for distributions to unitholders and the general partner for any one or more of the next four quarters.         The quarterly cash distributions applicable to 2010, 2009 and 2008, were as follows: <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="105"></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="111"></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="81"></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"> <div style="MARGIN-BOTTOM: 0pt; WIDTH: 53pt; BORDER-BOTTOM: #000000 1pt solid">Quarter Ended </div></th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Record Date </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Payment Date </th> <th style="FONT-FAMILY: times"> </th> <th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2">Amount Per Unit </th> <th style="FONT-FAMILY: times"> </th></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> December 31, 2010</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">February 7, 2011</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">February 14, 2011</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">0.65</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"> September 30, 2010</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">November 8, 2010</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">November 12, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> June 30, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 2, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 13, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</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"> March 31, 2010</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">May 3, 2010</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">May 14, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> December 31, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">February 5, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">February 12, 2010</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</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"> September 30, 2009</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">November 2, 2009</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">November 13, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> June 30, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 3, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 14, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</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"> March 31, 2009</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">May 4, 2009</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">May 15, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> December 31, 2008</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">February 6, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">February 13, 2009</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</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"> September 30, 2008</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">November 4, 2008</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">November 14, 2008</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.64</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr> <tr style="HEIGHT: 0px" valign="top" bgcolor="#CCEEFF"> <td style="FONT-FAMILY: times" valign="bottom"> June 30, 2008</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 4, 2008</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">August 15, 2008</td> <td style="FONT-FAMILY: times" valign="bottom"> </td> <td style="FONT-FAMILY: times" valign="bottom" align="right">$</td> <td style="FONT-FAMILY: times" valign="bottom" align="right">0.63</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"> March 31, 2008</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">May 5, 2008</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">May 15, 2008</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">0.60</td> <td style="FONT-FAMILY: times" valign="bottom"> </td></tr></table></div> </div> <ul> <li style="list-style: none"> Equity Offerings</li></ul>         On April 6, 2010, the Partnership completed a public offering of approximately 4.9 million newly issued common units, which included the exercise of the overallotment option by the underwriters, representing limited partner interests at a purchase price of $30.43 per common unit. Net proceeds of approximately $142.3 million were used to repay borrowings under its Credit Facility and to partially fund the Partnership's ongoing capital expenditure program.         On August 18, 2009, the Partnership completed a public offering of approximately 6.03 million newly issued common units, which included the exercise of the overallotment option by the underwriters, representing limited partner interests at a purchase price of $20.95 per common unit. Net proceeds of approximately $120.9 million were used to partially fund the Partnership's 2009 capital expenditure requirements, and the remainder was used to pay down borrowings under its Credit Facility.         On June 10, 2009, the Partnership completed a public offering of approximately 3.34 million newly issued common units, which included the exercise of the overallotment option by the underwriters, representing limited partner interests at a purchase price of $18.15 per common unit. Net proceeds of approximately $57.7 million were used to partially fund the Partnership's 2009 capital expenditure requirements, and the remainder was used to pay down borrowings under its Credit Facility.         On April 14, 2008, the Partnership completed a public offering of 5.75 million newly issued common units, which included the exercise of the overallotment option by the underwriters, representing limited partner interests at a purchase price of $31.15 per common unit. Net proceeds of approximately $171.4 million were used to pay down borrowings under its Credit Facility, and the remainder was used to partially fund the Partnership's 2008 capital expenditure requirements.</td></tr></table> 18. Equity         As described in Note 3, the Partnership acquired the Corporation through a merger of MWEP,falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes the formation, structure, control and ownership of the partnership. Disclosures related to accounts comprising partners' capital. Includes balances of general partners' capital account, limited partners' capital account, preferred partners' capital account and total partners' capital account and units outstanding; accumulated other comprehensive income; amount and nature of changes to amount of partner's capital and units outstanding by class, rights and privileges for each class of units; distribution policies and distributions paid by unit class; impact of and correction of an error in previously issued financial statements; limitations of partners' liability; redemption, conversion and distribution policies; and deferred compensation related to the issuance of units.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 10, 15 falsefalseEquity12EquityUnKnownUnKnownUnKnownUnKnownfalsetrue