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Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Apr. 08, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Apr. 01, 2025
Derivative [Line Items] |  |  |  |  |  |  |
Interest expense |  | $ 164,299 | $ 163,194 |  | $ 490,526 | $ 474,727 |
Santa Monica Business Park [Member] |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Debt | $ 200,000 |  |  |  |  |  |
2024 Unsecured Term Loan |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Debt | 100,000 |  |  |  |  |  |
Interest Rate Swap |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Derivative, Notional Amount | $ 300,000 | 900,000 |  | $ 900,000 | 900,000 |  | $ 300,000
Interest Rate Swap | Santa Monica Business Park and 2024 Unsecured Term Loan |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Derivative, Notional Amount |  | 300,000 |  | 300,000 | $ 300,000 |  |
Derivative, Fixed Interest Rate | 3.6775% |  |  |  |  |  |
Derivative, Maturity Date | Apr. 06, 2026 |  |  |  | Apr. 06, 2026 |  |
Interest expense |  | $ (500) |  | $ (1,000) |  |  |

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