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Lessee - Leases Narrative (Details) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | May 01, 2024 USD ($) ft² | Mar. 28, 2024 USD ($) ft² | Dec. 31, 2023 USD ($)
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Operating Lease, Payments |  |  |  |  | $ 390 | $ (282) |  |  |
Operating Lease, Right-of-Use Asset | [1] | $ 339,804 |  | $ 339,804 | 339,804 |  |  |  | $ 324,298
Lease liabilities - finance leases |  | 373,260 |  | 373,260 | 373,260 |  |  |  | 417,961
Finance Lease, Right-of-Use Asset |  | 372,896 |  | 372,896 | 372,896 |  |  |  | $ 401,680
Interest expense |  | (163,194) | $ (147,812) |  | (474,727) | $ (424,492) |  |  |
171 Dartmouth Street air rights [Member] |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Lessee, Operating Lease, Term of Contract |  |  |  |  |  |  |  | 90 years |
Lessee, Operating Lease, Discount Rate |  |  |  |  |  |  |  | 6.57% |
Net Present Value and Operating Lease Liability |  |  |  |  |  |  |  | $ 23,200 |
Operating Lease, Right-of-Use Asset |  |  |  |  |  |  |  | $ 23,900 |
Operating lease costs |  | $ 87 |  | $ 200 |  |  |  |  |
Land Subject to Ground Leases | ft² |  |  |  |  |  |  |  | 61,000 |
171 Dartmouth Street air rights [Member] | Base Rental Payment [Member] |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Operating Leases, Future Minimum Payments Due |  |  |  |  |  |  |  | $ 250 |
171 Dartmouth Street air rights [Member] | Additional Rental Payment |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Operating Leases, Future Minimum Payments Due |  |  |  |  |  |  |  | $ 500 |
The Skylyne |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Lessee, Finance Lease, Remaining Lease Term |  |  |  |  |  |  | 92 years |  |
Purchase Options, Land |  |  |  |  |  |  | $ 38,700 |  |
Lease liabilities - finance leases |  |  |  |  |  |  | 100 |  |
Finance Lease, Right-of-Use Asset |  |  |  |  |  |  | $ 0 |  |
Interest expense |  |  |  |  | $ 9,500 |  |  |  |
The Skylyne | Residential Building |  |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  | 331,000 |  |
Number of Units in Real Estate Property |  |  |  |  |  |  | 402 |  |
[1] | See Note 4.

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