XML 60 R52.htm IDEA: XBRL DOCUMENT v2.4.1.9
Investments in real estate Real estate asset sales (Details) (USD $)
 12 Months Ended 36 Months Ended
Dec. 31, 2014
property
sqft
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2014
property
sqft
Sep. 30, 2014
sqft
Real Estate Properties [Line Items]          
Number of properties sold 3are_DisposalGroupIncludingDiscontinuedOperationPropertiesSoldNumber     16are_DisposalGroupIncludingDiscontinuedOperationPropertiesSoldNumber  
Area of Real Estate Property 18,729,282us-gaap_AreaOfRealEstateProperty     18,729,282us-gaap_AreaOfRealEstateProperty  
Impairment of real estate $ 51,675,000us-gaap_ImpairmentOfRealEstate $ 0us-gaap_ImpairmentOfRealEstate $ 13,450,000us-gaap_ImpairmentOfRealEstate    
Gain on sales of real estate - land parcels 6,403,000us-gaap_GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes 4,824,000us-gaap_GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes 1,864,000us-gaap_GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes    
Various          
Real Estate Properties [Line Items]          
Number of Land Parcels Sold 6are_NumberofLandParcelsSold
/ us-gaap_StatementGeographicalAxis
= are_VariousMember		        
San Francisco, California          
Real Estate Properties [Line Items]          
Number of Land Parcels Sold 9are_NumberofLandParcelsSold
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		        
Number of Industrial Buildings Sold 7are_NumberofIndustrialBuildingsSold
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		        
Impairment of land parcels          
Real Estate Properties [Line Items]          
Impairment of real estate 24,700,000us-gaap_ImpairmentOfRealEstate
/ are_ImpairmentTypeAxis
= are_ImpairmentoflandparcelsMember		        
661 University Avenue | CANADA          
Real Estate Properties [Line Items]          
Area of Real Estate Property         780,540us-gaap_AreaOfRealEstateProperty
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_A661UniversityAvenueMember
/ us-gaap_StatementGeographicalAxis
= country_CA
661 University Avenue | Impairment of real estate | CANADA          
Real Estate Properties [Line Items]          
Impairment of real estate 16,600,000us-gaap_ImpairmentOfRealEstate
/ are_ImpairmentTypeAxis
= are_ImpairmentofrealestateMember
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_A661UniversityAvenueMember
/ us-gaap_StatementGeographicalAxis
= country_CA		        
Percentage of Impairment of Real Estate related to Foreign Exchange Rate, Estimated Transfer Taxes, and Closing Costs 75.00%are_PercentageofImpairmentofRealEstaterelatedtoForeignExchangeRateEstimatedTransferTaxesandClosingCosts
/ are_ImpairmentTypeAxis
= are_ImpairmentofrealestateMember
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_A661UniversityAvenueMember
/ us-gaap_StatementGeographicalAxis
= country_CA		        
500 Forbes Boulevard | San Francisco, California          
Real Estate Properties [Line Items]          
Area of Real Estate Property 155,685us-gaap_AreaOfRealEstateProperty
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		     155,685us-gaap_AreaOfRealEstateProperty
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		  
Annualized Revenues minus Operating Expenses 5,500,000are_AnnualizedRevenuesminusOperatingExpenses
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		        
Real Estate Project Yield 5.10%are_RealEstateProjectYield
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		     5.10%are_RealEstateProjectYield
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		  
500 Forbes Boulevard | Impairment of real estate | San Francisco, California          
Real Estate Properties [Line Items]          
Impairment of real estate 9,600,000us-gaap_ImpairmentOfRealEstate
/ are_ImpairmentTypeAxis
= are_ImpairmentofrealestateMember
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		        
Estimated Fair Value of Property, Less Cost to Sell 107,800,000are_FairValueofPropertyLessCosttoSell
/ are_ImpairmentTypeAxis
= are_ImpairmentofrealestateMember
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		     107,800,000are_FairValueofPropertyLessCosttoSell
/ are_ImpairmentTypeAxis
= are_ImpairmentofrealestateMember
/ us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis
= are_Number500ForbesBoulevardMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember		  
Income-producing assets | San Diego, California          
Real Estate Properties [Line Items]          
Number of properties sold 3are_DisposalGroupIncludingDiscontinuedOperationPropertiesSoldNumber
/ are_DispositionsAxis
= are_IncomeproducingassetsMember
/ us-gaap_StatementGeographicalAxis
= are_SanDiegoCaliforniaMember		        
Proceeds from sale of real estate 7,400,000us-gaap_ProceedsFromSaleOfRealEstate
/ are_DispositionsAxis
= are_IncomeproducingassetsMember
/ us-gaap_StatementGeographicalAxis
= are_SanDiegoCaliforniaMember		        
Gain (loss) on disposal of properties recognized 1,800,000us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
/ are_DispositionsAxis
= are_IncomeproducingassetsMember
/ us-gaap_StatementGeographicalAxis
= are_SanDiegoCaliforniaMember		        
Area of Real Estate Property 62,346us-gaap_AreaOfRealEstateProperty
/ are_DispositionsAxis
= are_IncomeproducingassetsMember
/ us-gaap_StatementGeographicalAxis
= are_SanDiegoCaliforniaMember		     62,346us-gaap_AreaOfRealEstateProperty
/ are_DispositionsAxis
= are_IncomeproducingassetsMember
/ us-gaap_StatementGeographicalAxis
= are_SanDiegoCaliforniaMember		  
Land parcels | Various          
Real Estate Properties [Line Items]          
Proceeds from sale of real estate 48,400,000us-gaap_ProceedsFromSaleOfRealEstate
/ are_DispositionsAxis
= are_LandparcelsMember
/ us-gaap_StatementGeographicalAxis
= are_VariousMember		        
Area of Real Estate Property 662,950us-gaap_AreaOfRealEstateProperty
/ are_DispositionsAxis
= are_LandparcelsMember
/ us-gaap_StatementGeographicalAxis
= are_VariousMember		     662,950us-gaap_AreaOfRealEstateProperty
/ are_DispositionsAxis
= are_LandparcelsMember
/ us-gaap_StatementGeographicalAxis
= are_VariousMember		  
Gain on sales of real estate - land parcels 6,400,000us-gaap_GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes
/ are_DispositionsAxis
= are_LandparcelsMember
/ us-gaap_StatementGeographicalAxis
= are_VariousMember		        
Land parcels | San Francisco, California          
Real Estate Properties [Line Items]          
Proceeds from sale of real estate $ 31,000,000us-gaap_ProceedsFromSaleOfRealEstate
/ are_DispositionsAxis
= are_LandparcelsMember
/ us-gaap_StatementGeographicalAxis
= are_SanFranciscoCaliforniaMember