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    <Log type="Info">'Monetary' elements on report '4030 - Disclosure - Real Estate Properties (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '4141 - Disclosure - SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION (Details 2)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 0010 - Statement - CONSOLIDATED BALANCE SHEETS</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">Process Flow-Through: 0015 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 0020 - Statement - CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2011'</Log>
    <Log type="Info">Process Flow-Through: 0040 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</Log>
  </Logs>
  <InputFiles>
    <File>snh-20121231.xml</File>
    <File>snh-20121231.xsd</File>
    <File>snh-20121231_cal.xml</File>
    <File>snh-20121231_def.xml</File>
    <File>snh-20121231_lab.xml</File>
    <File>snh-20121231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
