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Derivative Instruments and Hedging Activities (Narrative) (Details) $ in Thousands |  |  |  | 1 Months Ended | 8 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 14, 2023 USD ($) | Dec. 07, 2023 USD ($) Rate | May 02, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Oct. 26, 2023 USD ($)
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  | $ 579,572 | $ 437,139 | $ 423,346 |
Losses from interest rate contracts |  |  |  |  |  |  |  | (79) |  |  |
Interest rate swaps recorded upon consolidation |  |  |  |  |  |  |  | (7,337) | $ 0 | $ 0 |
Santa Monica Business Park [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage | [1] |  |  |  |  |  |  |  | 55.00% |  |
Joint Venture Partner [Member] | Santa Monica Business Park [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  | 45.00% |  |  |  |  |  |  |  |  |
Santa Monica Business Park [Member] | Mortgages [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt |  | $ 300,000 |  |  |  |  |  |  |  |  |
Santa Monica Business Park [Member] | Mortgages [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt |  | 300,000 |  |  |  |  |  |  |  |  |
325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties [Member] | Mortgages [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  |  |  |  |  |  |  |  | $ 600,000
Derivative, All in interest rate | Rate |  |  | 6.04% |  |  |  |  |  |  |  |
Interest Rate Swap |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Derivative, Inception Date |  |  |  | May 02, 2023 |  |  |  |  |  |  |
Derivative, Notional Amount |  |  | $ 600,000 | $ 1,200,000 | $ 2,100,000 | $ 2,100,000 | $ 2,100,000 | 2,100,000 |  |  |
Derivative, Average Fixed Interest Rate |  |  |  | 4.642% |  |  |  |  |  |  |
Derivative, Maturity Date |  |  |  | May 16, 2024 |  |  |  |  |  |  |
Derivative, Number of Instruments Held |  |  | 2 | 4 |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  | (4,200) |  |  |  |
Interest Rate Swap | Santa Monica Business Park [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Derivative, Notional Amount |  | $ 300,000 |  |  | 300,000 | 300,000 | 300,000 | $ 300,000 |  |  |
Derivative, Average Fixed Interest Rate |  | 2.679% |  |  |  |  |  |  |  |  |
Derivative, Maturity Date |  |  |  |  |  |  |  | Apr. 01, 2025 |  |  |
Derivative, Number of Instruments Held |  | 3 |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  | (400) |  |  |  |  |  |
Interest rate swaps recorded upon consolidation |  | $ 7,300 |  |  |  |  |  |  |  |  |
Interest Rate Swap | 325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties [Member] |  |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |
Derivative, Inception Date |  |  | Dec. 07, 2023 |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  | $ 600,000 |  | $ 600,000 | 600,000 | $ 600,000 | $ 600,000 |  |  |
Derivative, Average Fixed Interest Rate |  |  | 3.7925% |  |  |  |  |  |  |  |
Derivative, Maturity Date |  |  | Oct. 26, 2028 |  |  |  |  | Oct. 26, 2028 |  |  |
Derivative, Number of Instruments Held |  |  | 3 |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  | $ (400) |  |  |  |  |
[1] | During the year ended December 31, 2023, the Company completed the acquisition of its joint venture partner’s 45% ownership interest in Santa Monica Business Park, as described below in this Note 6 and Note 3.

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