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Organization and Basis of Presentation - Schedule of Commercial Office Properties (Details) $ in Billions | 9 Months Ended
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Sep. 30, 2018 USD ($) ft² building shares
Real estate properties |
Number of Properties | building | 84
Approximate Square Feet unaudited (sqft) | 30,584,045
Weighted Average Occupancy unaudited (as a percent) | 93.00%
Debt and preferred equity investments including investments held by unconsolidated joint ventures | $ | $ 2.1
Debt and preferred equity investments and other financing receivables included in other balance sheet items | $ | $ 0.1
Number of shares to be received on redemption of one unit of limited partnership interests (shares) | shares | 1
Commercial properties |
Real estate properties |
Number of Properties | building | 70
Approximate Square Feet unaudited (sqft) | 27,916,197
Weighted Average Occupancy unaudited (as a percent) | 93.10%
Residential |
Real estate properties |
Number of Properties | building | 14
Approximate Square Feet unaudited (sqft) | 2,667,848
Weighted Average Occupancy unaudited (as a percent) | 92.40%
Managed office properties |
Real estate properties |
Approximate Square Feet unaudited (sqft) | 336,000
Consolidated properties |
Real estate properties |
Number of Properties | building | 52
Approximate Square Feet unaudited (sqft) | 16,236,956
Consolidated properties | Commercial properties |
Real estate properties |
Number of Properties | building | 48
Approximate Square Feet unaudited (sqft) | 15,725,859
Consolidated properties | Residential |
Real estate properties |
Number of Properties | building | 4
Approximate Square Feet unaudited (sqft) | 511,097
Unconsolidated properties |
Real estate properties |
Number of Properties | building | 32
Approximate Square Feet unaudited (sqft) | 14,347,089
Unconsolidated properties | Commercial properties |
Real estate properties |
Number of Properties | building | 22
Approximate Square Feet unaudited (sqft) | 12,190,338
Unconsolidated properties | Residential |
Real estate properties |
Number of Properties | building | 10
Approximate Square Feet unaudited (sqft) | 2,156,751
Manhattan |
Real estate properties |
Number of Properties | building | 55
Approximate Square Feet unaudited (sqft) | 25,567,997
Weighted Average Occupancy unaudited (as a percent) | 93.20%
Manhattan | Office |
Real estate properties |
Number of Properties | building | 31
Approximate Square Feet unaudited (sqft) | 24,247,255
Weighted Average Occupancy unaudited (as a percent) | 94.50%
Manhattan | Retail |
Real estate properties |
Number of Properties | building | 14
Approximate Square Feet unaudited (sqft) | 664,797
Weighted Average Occupancy unaudited (as a percent) | 98.40%
Manhattan | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 9
Approximate Square Feet unaudited (sqft) | 655,945
Weighted Average Occupancy unaudited (as a percent) | 40.10%
Manhattan | Fee Interest |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 0
Weighted Average Occupancy unaudited (as a percent) | 0.00%
Manhattan | Residential |
Real estate properties |
Number of Properties | building | 14
Approximate Square Feet unaudited (sqft) | 2,667,848
Weighted Average Occupancy unaudited (as a percent) | 92.40%
Manhattan | Consolidated properties |
Real estate properties |
Number of Properties | building | 33
Approximate Square Feet unaudited (sqft) | 13,377,659
Manhattan | Consolidated properties | Office |
Real estate properties |
Number of Properties | building | 21
Approximate Square Feet unaudited (sqft) | 12,756,091
Manhattan | Consolidated properties | Retail |
Real estate properties |
Number of Properties | building | 5
Approximate Square Feet unaudited (sqft) | 312,623
Manhattan | Consolidated properties | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 7
Approximate Square Feet unaudited (sqft) | 308,945
Manhattan | Consolidated properties | Fee Interest |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Manhattan | Consolidated properties | Residential |
Real estate properties |
Number of Properties | building | 4
Approximate Square Feet unaudited (sqft) | 511,097
Manhattan | Consolidated properties | Dual property type, retail portion |
Real estate properties |
Approximate Square Feet unaudited (sqft) | 270,132
Manhattan | Consolidated properties | Dual property type, residential portion |
Real estate properties |
Approximate Square Feet unaudited (sqft) | 222,855
Manhattan | Unconsolidated properties |
Real estate properties |
Number of Properties | building | 22
Approximate Square Feet unaudited (sqft) | 12,190,338
Manhattan | Unconsolidated properties | Office |
Real estate properties |
Number of Properties | building | 10
Approximate Square Feet unaudited (sqft) | 11,491,164
Manhattan | Unconsolidated properties | Retail |
Real estate properties |
Number of Properties | building | 9
Approximate Square Feet unaudited (sqft) | 352,174
Manhattan | Unconsolidated properties | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 2
Approximate Square Feet unaudited (sqft) | 347,000
Manhattan | Unconsolidated properties | Fee Interest |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 0
Manhattan | Unconsolidated properties | Residential |
Real estate properties |
Number of Properties | building | 10
Approximate Square Feet unaudited (sqft) | 2,156,751
Suburban |
Real estate properties |
Number of Properties | building | 15
Approximate Square Feet unaudited (sqft) | 2,348,200
Weighted Average Occupancy unaudited (as a percent) | 91.70%
Suburban | Office |
Real estate properties |
Number of Properties | building | 13
Approximate Square Feet unaudited (sqft) | 2,295,200
Weighted Average Occupancy unaudited (as a percent) | 91.60%
Suburban | Retail |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 52,000
Weighted Average Occupancy unaudited (as a percent) | 100.00%
Suburban | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 1,000
Weighted Average Occupancy unaudited (as a percent) | 0.00%
Suburban | Residential |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Weighted Average Occupancy unaudited (as a percent) | 0.00%
Suburban | Consolidated properties |
Real estate properties |
Number of Properties | building | 15
Approximate Square Feet unaudited (sqft) | 2,348,200
Suburban | Consolidated properties | Office |
Real estate properties |
Number of Properties | building | 13
Approximate Square Feet unaudited (sqft) | 2,295,200
Suburban | Consolidated properties | Retail |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 52,000
Suburban | Consolidated properties | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 1
Approximate Square Feet unaudited (sqft) | 1,000
Suburban | Consolidated properties | Residential |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Suburban | Unconsolidated properties |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Suburban | Unconsolidated properties | Office |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Suburban | Unconsolidated properties | Retail |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Suburban | Unconsolidated properties | Development/Redevelopment |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0
Suburban | Unconsolidated properties | Residential |
Real estate properties |
Number of Properties | building | 0
Approximate Square Feet unaudited (sqft) | 0

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