XML 49 R45.htm IDEA: XBRL DOCUMENT
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Indebtedness (Details) (USD $) In Thousands, unless otherwise specified | 1 Months Ended | 12 Months Ended | 0 Months Ended | 1 Months Ended | 0 Months Ended | 1 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 31, 2014 | Apr. 30, 2014 | Dec. 31, 2014 item | Dec. 31, 2013 | Dec. 31, 2012 | Aug. 31, 2013 | Jun. 30, 2014 item | Sep. 30, 2013 item | Jun. 30, 2013 item | Feb. 28, 2015 property | Dec. 31, 2014 property | May 30, 2014 | May 31, 2014 | Feb. 26, 2015 | Jul. 31, 2012 | Dec. 31, 2011 | Aug. 31, 2012 item
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility, maximum borrowing capacity |  |  | $ 750,000 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity |  |  |  |  |  |  |  | $ 750,000 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity |  |  |  |  |  |
Number of public issues of unsecured senior notes |  |  | 6 snh_NumberOfPublicIssuesOfUnsecuredSeniorNotes |  |  |  |  |  |  |  | 6 snh_NumberOfPublicIssuesOfUnsecuredSeniorNotes |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 1,743,628 us-gaap_SeniorNotes | 1,093,337 us-gaap_SeniorNotes |  |  |  |  |  |  | 1,743,628 us-gaap_SeniorNotes |  |  |  |  |  |
Unsecured term loan facility |  |  | 1,750,000 us-gaap_DebtInstrumentFaceAmount | 1,100,000 us-gaap_DebtInstrumentFaceAmount |  |  |  |  |  |  | 1,750,000 us-gaap_DebtInstrumentFaceAmount |  |  |  |  |  |
Aggregate principal amount of mortgage debt |  |  | 611,369 us-gaap_SecuredDebt |  |  |  |  |  |  |  | 611,369 us-gaap_SecuredDebt |  |  |  |  |  |
Interest rate (as a percent) | 5.875%us-gaap_DebtInstrumentInterestRateStatedPercentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Carrying value of mortgaged properties |  |  | 5,254,761 us-gaap_RealEstateInvestmentPropertyNet | 4,422,865 us-gaap_RealEstateInvestmentPropertyNet |  |  |  |  |  |  | 5,254,761 us-gaap_RealEstateInvestmentPropertyNet |  |  |  |  |  |
Assumption of mortgage notes payable |  |  | 15,630 us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1 | 12,266 us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1 | 121,793 us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1 |  |  |  |  |  |  |  |  |  |  |  |
Repayment of debt | 14,700 us-gaap_ExtinguishmentOfDebtAmount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  | (12)us-gaap_GainsLossesOnExtinguishmentOfDebt | (797)us-gaap_GainsLossesOnExtinguishmentOfDebt | (6,349)us-gaap_GainsLossesOnExtinguishmentOfDebt |  |  |  |  |  |  |  |  |  |  |  |
Sale of senior unsecured notes |  |  | 350,000 us-gaap_ProceedsFromIssuanceOfDebt |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds after underwriting discounts from sale of senior unsecured notes |  | 644,889 us-gaap_ProceedsFromDebtNetOfIssuanceCosts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  | 80,000 us-gaap_LineOfCredit | 100,000 us-gaap_LineOfCredit |  |  |  |  |  |  | 80,000 us-gaap_LineOfCredit |  |  |  |  |  |
Net book value of the assets encumbered by capital leases |  |  | 18,237 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet | 18,627 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet |  |  |  |  |  |  | 18,237 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  | 6.28%us-gaap_DebtWeightedAverageInterestRate | 6.25%us-gaap_DebtWeightedAverageInterestRate |  |  |  |  |  |  | 6.28%us-gaap_DebtWeightedAverageInterestRate |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Extension period of revolving credit facility |  |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |  |  |
Option to increase the borrowing capacity under revolving credit facility |  |  | 1,500,000 snh_LineOfCreditFacilityOptionToIncreaseMaximumBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  | 1,500,000 snh_LineOfCreditFacilityOptionToIncreaseMaximumBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |
Interest rate, description |  |  |  | LIBOR |  | LIBOR |  |  |  |  |  |  |  |  |  |  |
Interest rate added to the base rate (as a percent) |  |  |  | 1.30%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  | 1.60%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |
Debt instrument, facility fee (as a percent) |  |  |  | 0.30%us-gaap_LineOfCreditFacilityCommitmentFeePercentage / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  | 0.35%us-gaap_LineOfCreditFacilityCommitmentFeePercentage / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, interest rate payable (as a percent) |  |  | 1.40%us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  | 1.40%us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  | 1.40%snh_DebtWeightedAverageInterestRateDuringThePeriod / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember | 1.60%snh_DebtWeightedAverageInterestRateDuringThePeriod / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember | 1.80%snh_DebtWeightedAverageInterestRateDuringThePeriod / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  |  | 538 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |  |  |
Principal repayment due until maturity |  |  | 0 snh_DebtInstrumentPrincipalRepaymentDueUntilMaturity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense and other associated costs incurred |  |  | 3,094 snh_InterestExpenseAndOtherAssociatedCostsIncurred / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember | 3,781 snh_InterestExpenseAndOtherAssociatedCostsIncurred / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember | 5,733 snh_InterestExpenseAndOtherAssociatedCostsIncurred / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  | 80,000 us-gaap_LineOfCredit / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  | 80,000 us-gaap_LineOfCredit / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  | 0 us-gaap_LineOfCredit / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |
Revolving credit facility, available amount |  |  | 750,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |  |  | 750,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember |  |  |  |  |  |
Unsecured revolving credit facility | Subsequent event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility, available amount |  |  | 750,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |  |  | 750,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = us-gaap_LineOfCreditMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |
Senior unsecured notes 4.30% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 250,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |  |  | 250,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |
Unsecured term loan facility |  |  | 250,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember | 250,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |  | 250,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |
Interest rate (as a percent) |  |  | 4.30%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |  |  | 4.30%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes4.30PercentMember |  |  |  |  |  |
Senior unsecured notes 6.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 200,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  |  |  |  |  | 200,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  |  |  |
Unsecured term loan facility |  |  | 200,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember | 200,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  |  |  |  | 200,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember | 300,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |
Interest rate (as a percent) |  |  | 6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  |  |  |  |  | 6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentMember |  |  |  |  |  |
Unsecured senior notes due 2021 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 300,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |  |  | 300,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |
Unsecured term loan facility |  |  | 300,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member | 300,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |  | 300,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |
Interest rate (as a percent) |  |  | 6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |  |  | 6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes6.75PercentDue2021Member |  |  |  |  |  |
Senior unsecured notes 5.625% due in 2042 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 350,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |  |  | 350,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |
Unsecured term loan facility |  |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |
Interest rate (as a percent) |  |  | 5.625%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |  |  | 5.625%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotes5.625PercentDue2042Member |  |  |  |  |  |
Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate principal amount of mortgage debt |  |  | 611,369 us-gaap_SecuredDebt / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  | 611,369 us-gaap_SecuredDebt / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |
Number of properties mortgaged |  |  | 45 snh_NumberOfRealEstatePropertiesCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  | 45 snh_NumberOfRealEstatePropertiesCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  | 28 snh_NumberOfRealEstatePropertiesCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember
Carrying value of mortgaged properties |  |  | 816,065 us-gaap_RealEstateInvestmentPropertyNet / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  | 816,065 us-gaap_RealEstateInvestmentPropertyNet / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |
Number of mortgage notes |  |  |  |  |  |  | 2 snh_NumberOfMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 2 snh_NumberOfMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 4 snh_NumberOfMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  |
Repayment of debt |  |  |  |  |  |  | 35,807 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 13,579 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 10,377 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  | 12 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 259 us-gaap_GainsLossesOnExtinguishmentOfDebt / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Properties released from mortgage as collateral |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11 snh_NumberOfRealEstatePropertiesReleasedFromMortgageCollateral / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember
Number of buildings mortgaged |  |  | 47 snh_NumberOfBuildingsCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  | 47 snh_NumberOfBuildingsCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  | 5.80%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 6.90%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember | 6.10%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember |  |  |  |  |  |  |  |
Mortgages | Significant Unobservable Inputs (Level 3) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 6.28%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |  |  | 6.28%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |
Assumption of mortgage notes payable |  |  | 15,630 us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1 / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of mortgage notes payable |  |  | 16,643 us-gaap_DebtInstrumentFairValue / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |  |  | 16,643 us-gaap_DebtInstrumentFairValue / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |
Increase (decrease) in outstanding principal balances |  |  | 1,013 us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mortgages | Subsequent event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) | 6.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  | 6.37%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |  | 6.02%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 6.37%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |
Repayment of debt | 11,900 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |  |  |  | 29,227 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 11,308 us-gaap_ExtinguishmentOfDebtAmount / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |
Number of properties encumbered under mortgage notes | 1 snh_NumberOfRealEstatePropertiesCollateralizedUnderMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  | 1 snh_NumberOfRealEstatePropertiesCollateralizedUnderMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |  | 1 snh_NumberOfRealEstatePropertiesCollateralizedUnderMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember | 1 snh_NumberOfRealEstatePropertiesCollateralizedUnderMortgageLoansRepaid / us-gaap_DebtInstrumentAxis = us-gaap_MortgagesMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember |  |  |  |  |  |
Capital leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 7.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |  |  | 7.70%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |
Number of properties mortgaged |  |  | 2 snh_NumberOfRealEstatePropertiesCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |  |  | 2 snh_NumberOfRealEstatePropertiesCollateralized / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |
Carrying value of mortgaged properties |  |  | 18,237 us-gaap_RealEstateInvestmentPropertyNet / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember | 18,627 us-gaap_RealEstateInvestmentPropertyNet / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |  | 18,237 us-gaap_RealEstateInvestmentPropertyNet / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |
Number of properties recorded under capital lease |  |  | 2 us-gaap_CapitalLeasedAssetsNumberOfUnits / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |  |  | 2 us-gaap_CapitalLeasedAssetsNumberOfUnits / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |
Capital leases |  |  | 12,770 us-gaap_CapitalLeaseObligations / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |  |  | 12,770 us-gaap_CapitalLeaseObligations / us-gaap_DebtInstrumentAxis = us-gaap_CapitalLeaseObligationsMember |  |  |  |  |  |
Senior unsecured notes due 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  | 400,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member | 400,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member |  |  |  |  |  |  |  | 400,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member |  |  |  |  |  |
Interest rate (as a percent) |  | 3.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member | 3.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member |  |  |  |  |  |  |  | 3.25%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019Member |  |  |  |  |  |
Senior unsecured notes due 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  | 250,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member | 250,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member |  |  |  |  |  |  |  | 250,000 us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member |  |  |  |  |  |
Interest rate (as a percent) |  | 4.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member | 4.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member |  |  |  |  |  |  |  | 4.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2024Member |  |  |  |  |  |
Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured term loan facility |  |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |  |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  | 350,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |
Interest rate (as a percent) |  |  | 1.60%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |  |  | 1.60%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |
Interest rate, description |  |  |  |  |  |  |  |  |  |  |  | LIBOR |  |  |  |  |
Interest rate added to the base rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 1.40%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember | 1.40%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |
Interest expense and other associated costs incurred |  |  | 3,263 snh_InterestExpenseAndOtherAssociatedCostsIncurred / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity that may be increased |  |  |  |  |  |  |  |  |  |  |  | 700,000 snh_DebtInstrumentMaximumBorrowingCapacityOptionToIncrease / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  | 1.60%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |  |  | 1.60%us-gaap_DebtWeightedAverageInterestRate / us-gaap_DebtInstrumentAxis = us-gaap_UnsecuredDebtMember |  |  |  |  |  |
Senior notes issued in April 2014 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds after underwriting discounts from sale of senior unsecured notes |  | $ 644,889 us-gaap_ProceedsFromDebtNetOfIssuanceCosts / us-gaap_DebtInstrumentAxis = snh_SeniorUnsecuredNotesDue2019AndDue2024Member |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

X
- Definition Represents the extension term of the debt agreement. + References No definition available. + Details
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- Definition Represents the maximum borrowing capacity to which loan may be expanded per the terms of the agreement, at the option of the reporting entity. + References No definition available. + Details
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- Definition Represents the amount of principal repayment of debt instrument due until maturity. + References No definition available. + Details
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- Definition Weighted average interest rate on debt during the period. + References No definition available. + Details
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- Definition Represents the interest expense and other associated costs related to debt instrument during the period. + References No definition available. + Details
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- Definition Represents the option to increase borrowings on the credit facility. + References No definition available. + Details
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- Definition Represents the number of buildings serving as collateral for debt as of the balance sheet date. + References No definition available. + Details
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- Definition Represents the number of mortgages repaid. + References No definition available. + Details
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- Definition Represents the number of public issues of unsecured senior notes. + References No definition available. + Details
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- Definition The number of real estate properties serving as collateral for debt as of the balance sheet date. + References No definition available. + Details
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- Definition The number of real estate properties serving as collateral for debt repaid as of the balance sheet date. + References No definition available. + Details
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- Definition The number of real estate properties released from mortgage as collateral for debt as of the balance sheet date. + References No definition available. + Details
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- Definition The number of units (items of property) under capital lease arrangements. + References No definition available. + Details
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- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737 + Details
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- Definition The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737 + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13476-108611 + Details
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- Definition Net increase or decrease in the carrying amount of the debt instrument for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph f -Article 4 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Gross amount of debt extinguished. + References No definition available. + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
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- Definition The effective interest rate at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination. + References No definition available. + Details
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- Definition The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt. + References No definition available. + Details
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- Definition Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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