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Investments in Unconsolidated Joint Ventures - Schedule of General Information on Joint Ventures (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
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Jan. 31, 2024 USD ($) | Sep. 30, 2024 USD ($) ft² | Mar. 31, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) ft² | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2021
General information on each joint venture |  |  |  |  |  |  |  |
Depreciable real estate reserves and impairment | $ |  | $ 0 |  | $ 389,000 | $ (65,839,000) | $ (305,527,000) |  |
Mortgages and other loans payable, net | $ |  | 1,643,992,000 |  |  | 1,643,992,000 |  | $ 1,491,319,000 |
625 Madison Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Depreciable real estate reserves and impairment | $ |  |  | $ 5,900,000 |  |  |  |  |
625 Madison Avenue | Preferred Equity (4) |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Carrying value of investment in leasehold interest | $ |  | 235,400,000 |  |  | $ 235,400,000 |  |  |
Average yield (as a percent) |  |  |  |  | 8.91% |  |  |
Joint venture |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Mortgages and other loans payable, net | $ |  | $ 13,653,311,000 |  |  | $ 13,653,311,000 |  | $ 14,799,277,000 |
Joint venture | 2 Herald Square |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Consideration transferred | $ | $ 0 |  |  |  |  |  |  |
Investment in joint venture, ownership percentage | 95.00% |  |  |  |  |  |  |
Prudential Real Estate Investors | Joint venture | 100 Park Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 49.90% |  |  | 49.90% |  |  |
Economic Interest (as a percent) |  | 49.90% |  |  | 49.90% |  |  |
Approximate Square Feet unaudited (sqft) |  | 834,000 |  |  | 834,000 |  |  |
Private Investors | Joint venture | 800 Third Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 60.52% |  |  | 60.52% |  |  |
Economic Interest (as a percent) |  | 60.52% |  |  | 60.52% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 3.37% |  |  | 3.37% |  |  |
Approximate Square Feet unaudited (sqft) |  | 526,000 |  |  | 526,000 |  |  |
Private Investors | Joint venture | 115 Spring Street |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 51.00% |  |  | 51.00% |  |  |
Economic Interest (as a percent) |  | 51.00% |  |  | 51.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 5.50% |  |  | 5.50% |  |  |
Approximate Square Feet unaudited (sqft) |  | 5,218 |  |  | 5,218 |  |  |
Private Investors | Joint venture | 625 Madison Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 90.93% |  |  | 90.93% |  |  |
Economic Interest (as a percent) |  | 90.93% |  |  | 90.93% |  |  |
Approximate Square Feet unaudited (sqft) |  | 591,123 |  |  | 591,123 |  |  |
New York State Teacher's Retirement System | Joint venture | 919 Third Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 51.00% |  |  | 51.00% |  |  |
Economic Interest (as a percent) |  | 51.00% |  |  | 51.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 6.11% |  |  | 6.11% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,454,000 |  |  | 1,454,000 |  |  |
Private Investor / Wharton Properties | Joint venture | 11 West 34th Street |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 30.00% |  |  | 30.00% |  |  |
Economic Interest (as a percent) |  | 30.00% |  |  | 30.00% |  |  |
Approximate Square Feet unaudited (sqft) |  | 17,150 |  |  | 17,150 |  |  |
Vornado Realty Trust | Joint venture | 280 Park Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 50.00% |  |  | 50.00% |  |  |
Economic Interest (as a percent) |  | 50.00% |  |  | 50.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 5.84% |  |  | 5.84% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,219,158 |  |  | 1,219,158 |  |  |
Wharton Properties | Joint venture | 1552-1560 Broadway |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 50.00% |  |  | 50.00% |  |  |
Approximate Square Feet unaudited (sqft) |  | 57,718 |  |  | 57,718 |  |  |
Wharton Properties | Joint venture | 650 Fifth Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 50.00% |  |  | 50.00% |  |  |
Economic Interest (as a percent) |  | 50.00% |  |  | 50.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 5.45% |  |  | 5.45% |  |  |
Approximate Square Feet unaudited (sqft) |  | 69,214 |  |  | 69,214 |  |  |
PGIM Real Estate | Joint venture | 11 Madison Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 60.00% |  |  | 60.00% |  |  |
Economic Interest (as a percent) |  | 60.00% |  |  | 60.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 3.84% |  |  | 3.84% |  |  |
Approximate Square Feet unaudited (sqft) |  | 2,314,000 |  |  | 2,314,000 |  |  |
National Pension Service of Korea / Hines Interest LP | Joint venture | One Vanderbilt Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 71.01% |  |  | 71.01% |  |  |
Economic Interest (as a percent) |  | 71.01% |  |  | 71.01% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 2.95% |  |  | 2.95% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,657,198 |  |  | 1,657,198 |  |  |
National Pension Service of Korea / Hines Interest LP | Joint venture | East 220 Street 42 |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Interest rate, fixed rate debt (as a percent) |  | 6.77% |  |  | 6.77% |  |  |
National Pension Service of Korea / Hines Interest LP | Joint venture | 5 Times Square |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Interest rate, fixed rate debt (as a percent) |  |  |  |  |  |  |  |
RXR Realty / New York REIT | Joint venture | Worldwide Plaza |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 24.95% |  |  | 24.95% |  |  |
Economic Interest (as a percent) |  | 24.95% |  |  | 24.95% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 3.98% |  |  | 3.98% |  |  |
Approximate Square Feet unaudited (sqft) |  | 2,048,725 |  |  | 2,048,725 |  |  |
Allianz Real Estate of America | Joint venture | 1515 Broadway |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 56.87% |  |  | 56.87% |  |  |
Economic Interest (as a percent) |  | 56.87% |  |  | 56.87% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 3.93% |  |  | 3.93% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,750,000 |  |  | 1,750,000 |  |  |
Israeli Institutional Investor | Joint venture | 2 Herald Square |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 95.00% |  |  | 95.00% |  |  |
Economic Interest (as a percent) |  | 95.00% |  |  | 95.00% |  |  |
Approximate Square Feet unaudited (sqft) |  | 369,000 |  |  | 369,000 |  |  |
A fund managed by Meritz Alternative Investment Management | Joint venture | 15 Beekman |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 20.00% |  |  | 20.00% |  |  |
Economic Interest (as a percent) |  | 20.00% |  |  | 20.00% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 5.99% |  |  | 5.99% |  |  |
Approximate Square Feet unaudited (sqft) |  | 221,884 |  |  | 221,884 |  |  |
A fund managed by Meritz Alternative Investment Management | Joint venture | East 220 Street 42 |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 51.00% |  |  | 51.00% |  |  |
Economic Interest (as a percent) |  | 51.00% |  |  | 51.00% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,135,000 |  |  | 1,135,000 |  |  |
Wells Fargo | Joint venture | 85 Fifth Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 36.27% |  |  | 36.27% |  |  |
Economic Interest (as a percent) |  | 36.27% |  |  | 36.27% |  |  |
Approximate Square Feet unaudited (sqft) |  | 12,946 |  |  | 12,946 |  |  |
National Pension Service of Korea / Hines Interest LP / International Investor | One Madison Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Investment in joint venture aggregate maximum ownership percentage |  |  |  |  |  |  |  | 25.00%
National Pension Service of Korea / Hines Interest LP / International Investor | Joint venture | One Madison Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 25.50% |  |  | 25.50% |  |  |
Economic Interest (as a percent) |  | 25.50% |  |  | 25.50% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 7.10% |  |  | 7.10% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,048,700 |  |  | 1,048,700 |  |  |
Korean Institutional Investor / Israeli Institutional Investor | 450 Park Avenue | Third-Party |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 49.90% |  |  | 49.90% |  |  |
Investment in joint venture, partners' ownership percentage |  | 25.00% |  |  | 25.00% |  |  |
Korean Institutional Investor / Israeli Institutional Investor | Joint venture | 450 Park Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 50.10% |  |  | 50.10% |  |  |
Economic Interest (as a percent) |  | 25.10% |  |  | 25.10% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 6.10% |  |  | 6.10% |  |  |
Approximate Square Feet unaudited (sqft) |  | 337,000 |  |  | 337,000 |  |  |
Investment in joint venture, ownership percentage |  | 25.10% |  |  | 25.10% |  |  |
RXR Realty led investment group | Joint venture | 5 Times Square |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 31.55% |  |  | 31.55% |  |  |
Economic Interest (as a percent) |  | 31.55% |  |  | 31.55% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,131,735 |  |  | 1,131,735 |  |  |
U.S. Affiliate of Mori Trust Co., Ltd | Joint venture | 245 Park Avenue |  |  |  |  |  |  |  |
General information on each joint venture |  |  |  |  |  |  |  |
Ownership Interest |  | 50.10% |  |  | 50.10% |  |  |
Economic Interest (as a percent) |  | 50.10% |  |  | 50.10% |  |  |
Interest rate, fixed rate debt (as a percent) |  | 4.30% |  |  | 4.30% |  |  |
Approximate Square Feet unaudited (sqft) |  | 1,782,793 |  |  | 1,782,793 |  |  |

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