XML 25 R34.htm IDEA: XBRL DOCUMENT v2.4.1.9
Investment in Real Estate (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Investment in Real Estate    
Land $ 80,398us-gaap_Land $ 78,983us-gaap_Land
Buildings and Improvements 928,562us-gaap_InvestmentBuildingAndBuildingImprovements 888,966us-gaap_InvestmentBuildingAndBuildingImprovements
Construction in progress 165,154us-gaap_DevelopmentInProcess 178,599us-gaap_DevelopmentInProcess
Total investments in real estate 1,174,114us-gaap_RealEstateInvestmentPropertyAtCost  
SV1 San Jose CA    
Investment in Real Estate    
Land 6,863us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SV1SanJoseCAMember		  
Buildings and Improvements 126,190us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SV1SanJoseCAMember		  
Construction in progress 902us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_SV1SanJoseCAMember		  
Total investments in real estate 133,955us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SV1SanJoseCAMember		  
SV2 Milpitas CA    
Investment in Real Estate    
Land 5,086us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SV2MilpitasCAMember		  
Buildings and Improvements 26,559us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SV2MilpitasCAMember		  
Construction in progress 700us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_SV2MilpitasCAMember		  
Total investments in real estate 32,345us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SV2MilpitasCAMember		  
SV3 Santa Clara CA    
Investment in Real Estate    
Land 3,972us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SV3SantaClaraCAMember		  
Buildings and Improvements 47,283us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SV3SantaClaraCAMember		  
Construction in progress 328us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_SV3SantaClaraCAMember		  
Total investments in real estate 51,583us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SV3SantaClaraCAMember		  
SV4 Santa Clara CA    
Investment in Real Estate    
Land 4,501us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SV4SantaClaraCAMember		  
Buildings and Improvements 89,230us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SV4SantaClaraCAMember		  
Construction in progress 223us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_SV4SantaClaraCAMember		  
Total investments in real estate 93,954us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SV4SantaClaraCAMember		  
SV5 Santa Clara CA    
Investment in Real Estate    
Land 2,544us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SV5SantaClaraCAMember		  
Buildings and Improvements 20,430us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SV5SantaClaraCAMember		  
Total investments in real estate 22,974us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SV5SantaClaraCAMember		  
Santa Clara Campus Properties Santa Clara CA    
Investment in Real Estate    
Land 8,173us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_SantaClaraCampusPropertiesSantaClaraCAMember		  
Buildings and Improvements 8,182us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_SantaClaraCampusPropertiesSantaClaraCAMember		  
Construction in progress 14,491us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_SantaClaraCampusPropertiesSantaClaraCAMember		  
Total investments in real estate 30,846us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_SantaClaraCampusPropertiesSantaClaraCAMember		  
BO1 Somerville MA    
Investment in Real Estate    
Land 5,154us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_BO1SomervilleMAMember		  
Buildings and Improvements 81,777us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_BO1SomervilleMAMember		  
Construction in progress 295us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_BO1SomervilleMAMember		  
Total investments in real estate 87,226us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_BO1SomervilleMAMember		  
NY1 New York NY    
Investment in Real Estate    
Buildings and Improvements 34,094us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_NY1NewYorkNYMember		  
Construction in progress 125us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_NY1NewYorkNYMember		  
Total investments in real estate 34,219us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_NY1NewYorkNYMember		  
NY2 Secaucus NJ    
Investment in Real Estate    
Land 1,158us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_NY2SecaucusNJMember		  
Buildings and Improvements 45,364us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_NY2SecaucusNJMember		  
Construction in progress 77,655us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_NY2SecaucusNJMember		  
Total investments in real estate 124,177us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_NY2SecaucusNJMember		  
VA1 Reston VA    
Investment in Real Estate    
Land 6,903us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_VA1RestonVAMember		  
Buildings and Improvements 113,168us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_VA1RestonVAMember		  
Construction in progress 4,268us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_VA1RestonVAMember		  
Total investments in real estate 124,339us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_VA1RestonVAMember		  
VA2 Reston VA    
Investment in Real Estate    
Land 1,356us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_VA2RestonVAMember		  
Buildings and Improvements 32,401us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_VA2RestonVAMember		  
Construction in progress 56,983us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_VA2RestonVAMember		  
Total investments in real estate 90,740us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_VA2RestonVAMember		  
DC1 Washington DC    
Investment in Real Estate    
Buildings and Improvements 7,924us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_DC1WashingtonDCMember		  
Construction in progress 169us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_DC1WashingtonDCMember		  
Total investments in real estate 8,093us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_DC1WashingtonDCMember		  
CH1 Chicago IL    
Investment in Real Estate    
Land 5,493us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_CH1ChicagoILMember		  
Buildings and Improvements 84,260us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_CH1ChicagoILMember		  
Construction in progress 5,434us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_CH1ChicagoILMember		  
Total investments in real estate 95,187us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_CH1ChicagoILMember		  
LA1 Los Angeles CA    
Investment in Real Estate    
Buildings and Improvements 62,164us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_LA1LosAngelesCAMember		  
Construction in progress 2,508us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_LA1LosAngelesCAMember		  
Total investments in real estate 64,672us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_LA1LosAngelesCAMember		  
LA2 Los Angeles CA    
Investment in Real Estate    
Land 28,467us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_LA2LosAngelesCAMember		  
Buildings and Improvements 135,587us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_LA2LosAngelesCAMember		  
Construction in progress 1,025us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_LA2LosAngelesCAMember		  
Total investments in real estate 165,079us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_LA2LosAngelesCAMember		  
MI1 Miami FL    
Investment in Real Estate    
Land 728us-gaap_Land
/ us-gaap_RealEstatePropertiesAxis
= cor_MI1MiamiFLMember		  
Buildings and Improvements 10,305us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_MI1MiamiFLMember		  
Construction in progress 30us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_MI1MiamiFLMember		  
Total investments in real estate 11,063us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_MI1MiamiFLMember		  
DE1 Denver CO    
Investment in Real Estate    
Buildings and Improvements 2,604us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_DE1DenverCOMember		  
Construction in progress 13us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_DE1DenverCOMember		  
Total investments in real estate 2,617us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_DE1DenverCOMember		  
DE2 Denver CO    
Investment in Real Estate    
Buildings and Improvements 1,040us-gaap_InvestmentBuildingAndBuildingImprovements
/ us-gaap_RealEstatePropertiesAxis
= cor_DE2DenverCOMember		  
Construction in progress 5us-gaap_DevelopmentInProcess
/ us-gaap_RealEstatePropertiesAxis
= cor_DE2DenverCOMember		  
Total investments in real estate $ 1,045us-gaap_RealEstateInvestmentPropertyAtCost
/ us-gaap_RealEstatePropertiesAxis
= cor_DE2DenverCOMember