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Noncontrolling Interests (Property Partnerships) (Narrative) (Details) - USD ($) $ in Thousands | Aug. 27, 2025 | Aug. 26, 2025 | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | --- | --- | ---
Noncontrolling Interest [Line Items] |  |  |  |
Noncontrolling Interest in Limited Partnerships |  |  | $ 1,970,949 | $ 1,933,545
343 Madison Avenue |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests | $ 43,500 |  |  |
Gain on Sale of Investments | $ 0 |  |  |
Variable Interest Entity, Ownership Percentage |  | 55.00% |  |
343 Madison Avenue | Minority Interest |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |
Subsidiary, Ownership Percentage, Noncontrolling Owner | 45.00% |  |  |

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