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Derivative Instruments and Hedging Activities (Details) - Interest Rate Swap - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 27, 2024	Dec. 31, 2023
Derivative [Line Items]
Derivative, Notional Amount	$ 900,000
Cash Flow Hedges Derivative Instruments at Fair Value, Net	$ (10,191)		$ 1,976
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
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	$ (12,600)
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
Cash Flow Hedges Derivative Instruments at Fair Value, Net	$ (11,801)
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	$ 1,610
2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Swap Type	Interest Rate Swaps
Derivative, Notional Amount	$ 100,000
Derivative, Maturity Date	Apr. 01, 2025
Derivative, Fixed Interest Rate		2.688%
Fair Value Hedge Assets	$ 799
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%
Minimum [Member] | Santa Monica Business Park [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.661%
Minimum [Member] | 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%
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%
Maximum [Member] | Santa Monica Business Park [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%
Maximum [Member] | 2024 Unsecured Term Loan
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.688%

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