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    <Log type="Info">'Monetary' elements on report '40100 - Disclosure - Stock-based Compensation and Equity (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '40130 - Disclosure - Segment Reporting (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '40140 - Disclosure - Discontinued Operations (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 0110 - Statement - CONSOLIDATED BALANCE SHEETS (UNAUDITED)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">Process Flow-Through: 01110 - Statement - CONSOLIDATED BALANCE SHEETS (UNAUDITED) (PARENTHETICALS)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">Process Flow-Through: 01200 - Statement - CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)</Log>
    <Log type="Info">Process Flow-Through: 01300 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</Log>
    <Log type="Info">Process Flow-Through: 01400 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</Log>
    <Log type="Info">Process Flow-Through: 40075 - Statement - Fair Value Measurements (Details 1)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2010'</Log>
  </Logs>
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    <File>wpc-20110630.xml</File>
    <File>wpc-20110630.xsd</File>
    <File>wpc-20110630_cal.xml</File>
    <File>wpc-20110630_def.xml</File>
    <File>wpc-20110630_lab.xml</File>
    <File>wpc-20110630_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
