XML 45 R40.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Mortgages Payable (Details) (USD $) | 0 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Feb. 28, 2014 Extensions | Dec. 31, 2014 | Dec. 31, 2013
Mortgage Loans on Real Estate [Line Items] |  |  |
Notes Payable |  | $ 1,032,780,000 us-gaap_NotesPayable | $ 1,049,959,000 us-gaap_NotesPayable
Net carrying value of real estate collaterizing the debt |  | 706,791,000 alx_PledgedAssetsSeperatelyReportedRealEstatePledgedAsCollateralAtCarryingValue |
Repayments of Long-term Debt [Abstract] |  |  |
2015 |  | 401,439,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths |
2016 |  | 3,440,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo |
2017 |  | 3,707,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree |
2018 |  | 324,194,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour |
2019 |  | 0 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive |
Thereafter |  | 300,000,000 us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive |
Rego Park 1 Shopping [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Percentage of cash mortgage collateralized |  | 100.00%alx_PercentageOfCashMortgageCollateralized / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark1ShoppingMember |
Rego Park 1 Shopping [Member] | Mortgages [Member] | Secured [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Debt Instrument Maturity Date String |  | 2015-03 |
Interest rate (in percentage) |  | 0.40%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark1ShoppingMember |
Notes Payable |  | 78,246,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark1ShoppingMember | 78,246,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark1ShoppingMember
Rego Park 2 Property [Member] | Mortgages [Member] | Secured [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Debt Instrument Maturity Date String |  | 2018-11 |
Interest rate (in percentage) |  | 2.02%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark2PropertyMember |
Notes Payable |  | 266,534,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark2PropertyMember | 269,496,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark2PropertyMember
Basis spread over LIBOR (in percentage) |  | 1.85%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_RegoPark2PropertyMember |
Lexington Avenue Property [Member] | Retail Space [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Notes Payable |  | 320,000,000 us-gaap_NotesPayable / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |
Mortgage Loan Converted To Recourse |  | 75,000,000 alx_MortgageLoanConvertedToRecourse / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |
Lexington Avenue Property [Member] | Mortgages [Member] | Secured [Member] | Office Space [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Debt Instrument Maturity Date String | 2017-03 | 2021-03 |
Interest rate (in percentage) |  | 1.11%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |
Notes Payable |  | 300,000,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember | 314,217,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember
Basis spread over LIBOR (in percentage) | 0.95%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |  |
Proceeds from (Repayments of) Debt | 300,000,000 us-gaap_ProceedsFromRepaymentsOfDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |  |
Number Of Extensions Available | 4 alx_NumberOfExtensionsAvailable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |  |
Length Of Extension Available | 1 year |  |
Derivative Liability Notional Amount | 300,000,000 us-gaap_DerivativeLiabilityNotionalAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |  |
Derivative cap interest rate, LIBOR | 6.00%us-gaap_DerivativeCapInterestRate / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_OfficeBuildingMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |  |
Lexington Avenue Property [Member] | Mortgages [Member] | Secured [Member] | Retail Space [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Debt Instrument Maturity Date String |  | 2015-07 |
Interest rate (in percentage) |  | 4.93%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |
Notes Payable |  | 320,000,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember | 320,000,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember
Lexington Avenue Property [Member] | Mortgages [Member] | Secured [Member] | Retail Space [Member] | Maximum [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Mortgage Loan Converted To Recourse |  | 75,000,000 alx_MortgageLoanConvertedToRecourse / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis = us-gaap_RetailSiteMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_LexingtonAvenuePropertyMember |
Paramus Property [Member] | Mortgages [Member] | Secured [Member] |  |  |
Mortgage Loans on Real Estate [Line Items] |  |  |
Debt Instrument Maturity Date String |  | 2018-10 |
Interest rate (in percentage) |  | 2.90%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_ParamusPropertyMember |
Notes Payable |  | $ 68,000,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_ParamusPropertyMember | $ 68,000,000 us-gaap_NotesPayable / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_MortgageLoansOnRealEstateDescriptionLoanCategoryAxis = us-gaap_MortgagesMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = alx_ParamusPropertyMember

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