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Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Derivative [Line Items]
Losses from interest rate contracts	$ 0	$ 0
Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	900,000
Interest rate swaps	$ (4,079)		$ 5,252
Interest Rate Swap | 325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties [Member]
Derivative [Line Items]
Derivative, Swap Type	Interest Rate Swaps
Derivative, Notional Amount	$ 600,000
Derivative, Maturity Date	Oct. 26, 2028
Fair Value Hedge Assets	$ (4,079)
Interest Rate Swap | 325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties and 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Notional Amount	700,000
Interest rate swaps	$ (4,079)
Interest Rate Swap | Santa Monica Business Park [Member]
Derivative [Line Items]
Derivative, Swap Type	Interest Rate Swaps
Derivative, Notional Amount	$ 200,000
Derivative, Maturity Date	Apr. 01, 2025
Fair Value Hedge Assets	$ 0
Interest Rate Swap | 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Swap Type	Interest Rate Swaps
Derivative, Notional Amount	$ 100,000
Derivative, Maturity Date	Apr. 01, 2025
Fair Value Hedge Assets	$ 0
Interest Rate Swap | Minimum [Member] | 325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.79%
Interest Rate Swap | Minimum [Member] | Santa Monica Business Park [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.661%
Interest Rate Swap | Minimum [Member] | 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%
Interest Rate Swap | Maximum [Member] | 325 Main Street, 355 Main Street, 90 Broadway and Kendall Center Green Garage Properties [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.798%
Interest Rate Swap | Maximum [Member] | Santa Monica Business Park [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%
Interest Rate Swap | Maximum [Member] | 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%

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Fair value of all asset derivatives designated as cash flow hedging instruments.

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Net fair value of all derivative instruments designated as cash flow hedging instruments, which is ordinarily reflected within other comprehensive income.

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Fixed interest rate related to the interest rate derivative.

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