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Summary Of Significant Accounting Policies (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Interest capitalized |  | $ 42,633,000 |  | $ 52,130,000 |  | $ 53,097,000
Salaries And Related Costs Capitalized |  | 16,100,000 |  | 16,100,000 |  | 13,700,000
Cash FDIC Insured Limit |  | 250,000 |  |  |  |
Separate Unrestricted Cash For Deferred Compensation Plan. |  | 36,100,000 |  | 32,300,000 |  |
Gains (losses) from investments in securities |  | $ 5,556,000 |  | (6,453,000) |  | 5,626,000
Accounts Receivable, Collection Period Expected |  | 1 |  |  |  |
Straight Line Rent Adjustments |  | $ 99,100,000 |  | 108,000,000 |  | 104,300,000
Above and below market rent adjustments, net |  | $ 19,200,000 |  | 9,100,000 |  | 4,200,000
REIT Distribution Requirement |  | 90.00% |  |  |  |
Company's Taxable Income Distribution |  | 100.00% |  |  |  |
Unrealized Gain (Loss) on Investments |  | $ 239,000 |  | (150,000) |  | 0
Losses from interest rate contracts |  | 79,000 |  |  |  |
Prepaid Expense and Other Assets |  | 64,230,000 |  | 43,589,000 |  |
Carrying Amount [Member] |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
3-Month United States Treasury Bills | [1] | 302,746,000 |  | 0 |  |
Unconsolidated Joint Ventures [Member] |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Straight Line Rent Adjustments |  | 28,700,000 |  | 62,900,000 |  | 17,200,000
Above and below market rent adjustments, net |  | 800,000 |  | 400,000 |  | 400,000
Impairment loss on investment |  | $ (272,603,000) | [2] | (50,705,000) | [2] | $ 0
Unconsolidated Joint Ventures [Member] | Dock 72 [Member] |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Impairment loss on investment |  |  |  | 50,700,000 |  |
Interest Rate Cap |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Derivative, Number of Instruments Held |  | 2 |  |  |  |
Derivative, Notional Amount |  | $ 600,000,000 |  |  |  |
Losses from interest rate contracts |  | 79,000 |  |  |  |
Environmental Focused Investment Fund |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Unrealized Gain (Loss) on Investments |  | 200,000 |  | (200,000) |  |
Prepaid Expense and Other Assets |  | $ 4,600,000 |  | 2,400,000 |  |
US Treasury Bill Securities |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
U.S. Treasury Bill, Term of Contract |  | 3 months |  |  |  |
Cash Equivalents, at Carrying Value |  |  |  | $ 0 |  |
3-Month United States Treasury Bills |  | $ 302,700,000 |  |  |  |
Unconsolidated Properties | Platform Sixteen, Three Six Zero Park Avenue South, Two Zero Zero Fifth Avenue and Safeco Plaza |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Number of real estate properties |  | 4 |  |  |  |
Unconsolidated Properties | Unconsolidated Joint Ventures [Member] |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |
Impairment loss on investment |  | $ 272,600,000 |  |  |  |
[1] | Per the guidance in ASC 326, the Company concluded that the risk of nonpayment is nonexistent because the U.S. Government has a long history with no credit losses and therefore, no credit loss allowance was recorded.
[2] | During the year ended December 31, 2023, the Company recognized an other-than-temporary impairment loss on its investments in Platform 16, 360 Park Avenue South, 200 Fifth Avenue and Safeco Plaza of approximately $155.2 million, $54.0 million, $33.4 million and $29.9 million, respectively, as described below in this Note 6. During the year ended December 31, 2022, the Company recognized an other-than-temporary impairment loss on its investment in the unconsolidated joint venture that owns Dock 72 in Brooklyn, New York totaling approximately $50.7 million.

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