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Organization of The Parent Company and The Operating Partnership - Summary of Core Portfolio of Operating Properties and Excludes Development and Redevelopment Properties Under Construction (Details) | Mar. 31, 2018 ft² property
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Real Estate Properties [Line Items] |
Number of Properties | property | 94
Rentable Square Feet | ft² | 16,501,024
Office Properties [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 82
Rentable Square Feet | ft² | 15,004,862
Mixed-use Properties [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 5
Rentable Square Feet | ft² | 646,741
Retail Properties [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 1
Rentable Square Feet | ft² | 17,884
Core Properties [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 88
Rentable Square Feet | ft² | 15,669,487
Development Projects [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 2
Rentable Square Feet | ft² | 247,818
Redevelopment Projects [Member] |
Real Estate Properties [Line Items] |
Number of Properties | property | 4
Rentable Square Feet | ft² | 583,719

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- Definition Area of a real estate property. + References No definition available. + Details
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- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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