<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Version>2.2.0.7</Version>
  <MyReports>
    <Report>
      <IsDefault>true</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>00 - Document - Document and Entity Information</LongName>
      <ShortName>Document and Entity Information</ShortName>
      <Role>http://amb.com/role/DocumentAndEntityInformation</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R1.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0110 - Statement - Consolidated Balance Sheets (Unaudited)</LongName>
      <ShortName>Consolidated Balance Sheets (Unaudited)</ShortName>
      <Role>http://amb.com/role/BalanceSheets</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R2.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0111 - Statement - Consolidated Balance Sheets (Unaudited) (Parenthetical)</LongName>
      <ShortName>Consolidated Balance Sheets (Unaudited) (Parenthetical)</ShortName>
      <Role>http://amb.com/role/BalanceSheetsParenthetical</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R3.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0120 - Statement - Consolidated Statements of Operations (Unaudited)</LongName>
      <ShortName>Consolidated Statements of Operations (Unaudited)</ShortName>
      <Role>http://amb.com/role/StatementsOfOperations</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R4.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0130 - Statement - Consolidated Statement of Equity (Unaudited)</LongName>
      <ShortName>Consolidated Statement of Equity (Unaudited)</ShortName>
      <Role>http://amb.com/role/StatementOfEquity</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R5.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0140 - Statement - Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ShortName>Consolidated Statements of Cash Flows (Unaudited)</ShortName>
      <Role>http://amb.com/role/CashFlowsStatements</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R6.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0201 - Disclosure - Organization and Formation of the Parent Company and the Operating Partnership</LongName>
      <ShortName>Organization and Formation of the Parent Company and the Operating Partnership</ShortName>
      <Role>http://amb.com/role/OrganizationAndFormationOfParentCompanyAndOperatingPartnership</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R7.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0202 - Disclosure - Interim Financial Statements</LongName>
      <ShortName>Interim Financial Statements</ShortName>
      <Role>http://amb.com/role/InterimFinancialStatements</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R8.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0203 - Disclosure - Real Estate Acquisition and Development Activity</LongName>
      <ShortName>Real Estate Acquisition and Development Activity</ShortName>
      <Role>http://amb.com/role/RealEstateAcquisitionAndDevelopmentActivity</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R9.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0204 - Disclosure - Development Profits, Gains from Sale or Contribution of Real Estate Interests and Discontinued Operations</LongName>
      <ShortName>Development Profits, Gains from Sale or Contribution of Real Estate Interests and Discontinued Operations</ShortName>
      <Role>http://amb.com/role/DevelopmentProfitsGainsFromSaleOrContributionOfRealEstateInterestsAndDiscontinuedOperations</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R10.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0205 - Disclosure - Debt of the Parent Company</LongName>
      <ShortName>Debt of the Parent Company</ShortName>
      <Role>http://amb.com/role/DebtOfParentCompany</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R11.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0206 - Disclosure - Debt of the Operating Partnership</LongName>
      <ShortName>Debt of the Operating Partnership</ShortName>
      <Role>http://amb.com/role/DebtOfOperatingPartnership</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R12.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0207 - Disclosure - Noncontrolling Interests in the Parent Company</LongName>
      <ShortName>Noncontrolling Interests in the Parent Company</ShortName>
      <Role>http://amb.com/role/NoncontrollingInterestsInParentCompany</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R13.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0208 - Disclosure - Noncontrolling Interests in the Operating Partnership</LongName>
      <ShortName>Noncontrolling Interests in the Operating Partnership</ShortName>
      <Role>http://amb.com/role/NoncontrollingInterestsInOperatingPartnership</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R14.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0209 - Disclosure - Investments in Unconsolidated Joint Ventures</LongName>
      <ShortName>Investments in Unconsolidated Joint Ventures</ShortName>
      <Role>http://amb.com/role/InvestmentsInUnconsolidatedJointVentures</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R15.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0210 - Disclosure - Stockholders' Equity of the Parent Company</LongName>
      <ShortName>Stockholders' Equity of the Parent Company</ShortName>
      <Role>http://amb.com/role/StockholdersEquityOfParentCompany</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R16.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0211 - Disclosure - Partners' Capital of the Operating Partnership</LongName>
      <ShortName>Partners' Capital of the Operating Partnership</ShortName>
      <Role>http://amb.com/role/PartnersCapitalOfOperatingPartnership</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R17.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0212 - Disclosure - Income (Loss) Per Share and Unit</LongName>
      <ShortName>Income (Loss) Per Share and Unit</ShortName>
      <Role>http://amb.com/role/IncomeLossPerShareAndUnit</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R18.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0213 - Disclosure - Segment Information</LongName>
      <ShortName>Segment Information</ShortName>
      <Role>http://amb.com/role/SegmentInformation</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R19.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0214 - Disclosure - Commitments and Contingencies</LongName>
      <ShortName>Commitments and Contingencies</ShortName>
      <Role>http://amb.com/role/CommitmentsAndContingencies</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R20.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0215 - Disclosure - Derivatives and Hedging Activities</LongName>
      <ShortName>Derivatives and Hedging Activities</ShortName>
      <Role>http://amb.com/role/DerivativesAndHedgingActivities</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R21.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Sheet</ReportType>
      <LongName>0216 - Disclosure - Subsequent Events</LongName>
      <ShortName>Subsequent Events</ShortName>
      <Role>http://amb.com/role/SubsequentEvents</Role>
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName>R22.xml</XmlFileName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <ReportType>Book</ReportType>
      <LongName>All Reports</LongName>
      <ShortName>All Reports</ShortName>
      <Role />
      <ContainEmbeddedReports>false</ContainEmbeddedReports>
      <XmlFileName />
    </Report>
  </MyReports>
  <EntityCount>1</EntityCount>
  <ContextCount>75</ContextCount>
  <SegmentCount>14</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <UnitCount>3</UnitCount>
  <ElementCount>209</ElementCount>
  <FootnotesReported>false</FootnotesReported>
  <TuplesReported>false</TuplesReported>
  <ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member_Accumulated_Other_Comprehensive_Income_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>ThreeMonthsEnded_30Jun2009_Parent_Company_Member</ContextName>
      <ElementCount>37</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Retained_Earnings_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member_Common_Stock_Member_General_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Subsidiaries_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member_Noncontrolling_Interest_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_02Aug2010</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member</ContextName>
      <ElementCount>85</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2009_Subsidiaries_Member</ContextName>
      <ElementCount>77</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>January-01-2010_June-30-2010</ContextName>
      <ElementCount>28</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2008_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Series_O_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member_Common_Stock_Member_Limited_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Preferred_Stock_Member_Subsidiaries_Member_General_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Noncontrolling_Interest_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Series_O_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Series_P_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Accumulated_Other_Comprehensive_Income_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Additional_Paid_In_Capital_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Preferred_Stock_Member_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Series_P_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>ThreeMonthsEnded_30Jun2010_Subsidiaries_Member</ContextName>
      <ElementCount>40</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Series_P_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Preferred_Stock_Member_Subsidiaries_Member_General_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member</ContextName>
      <ElementCount>40</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Preferred_Stock_Member_Subsidiaries_Member_General_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member</ContextName>
      <ElementCount>36</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member</ContextName>
      <ElementCount>40</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Noncontrolling_Interest_Member</ContextName>
      <ElementCount>5</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Series_O_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Common_Stock_Member_General_Partner_Member</ContextName>
      <ElementCount>14</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Common_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Retained_Earnings_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2009</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Series_O_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2009_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2009_Parent_Company_Member</ContextName>
      <ElementCount>75</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Subsidiaries_Member_Series_P_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member_Common_Stock_Member</ContextName>
      <ElementCount>8</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Series_P_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Additional_Paid_In_Capital_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Series_O_Preferred_Stock_Member_Subsidiaries_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member</ContextName>
      <ElementCount>87</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>ThreeMonthsEnded_30Jun2009_Subsidiaries_Member</ContextName>
      <ElementCount>39</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member_Common_Stock_Member_General_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Common_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Noncontrolling_Interest_Member_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Parent_Company_Member_Series_P_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Accumulated_Other_Comprehensive_Income_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member_Retained_Earnings_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Common_Stock_Member_Limited_Partner_Member</ContextName>
      <ElementCount>5</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Subsidiaries_Member_Noncontrolling_Interest_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>TwelveMonthsEnded_31Dec2009_Subsidiaries_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Preferred_Stock_Member_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member_Common_Stock_Member_Limited_Partner_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2008_Parent_Company_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2009_Subsidiaries_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Preferred_Stock_Member_Parent_Company_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>ThreeMonthsEnded_30Jun2010_Parent_Company_Member</ContextName>
      <ElementCount>38</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Series_O_Preferred_Stock_Member_Parent_Company_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_30Jun2010_Parent_Company_Member_Series_M_Preferred_Stock_Member</ContextName>
      <ElementCount>6</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Parent_Company_Member_Additional_Paid_In_Capital_Member</ContextName>
      <ElementCount>7</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>SixMonthsEnded_30Jun2010_Subsidiaries_Member_Series_L_Preferred_Stock_Member</ContextName>
      <ElementCount>2</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member</ContextName>
      <ElementCount>36</ElementCount>
    </ContextSummary>
    <ContextSummary>
      <ContextName>BalanceAsOf_31Dec2009_Subsidiaries_Member_Noncontrolling_Interest_Member</ContextName>
      <ElementCount>1</ElementCount>
    </ContextSummary>
  </ContextSummary>
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
