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Commitments And Contingencies (Details) $ in Thousands | 9 Months Ended |  |  |
--- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) ft² Real_Estate_Properties | Dec. 31, 2023 USD ($) | Oct. 02, 2023 USD ($) ft² | Jan. 05, 2023 ft²
Commitments And Contingencies [Line Items] |  |  |  |
Letter of credit and performance obligations | $ 21,000 |  |  |
Note receivable, net | 3,937 | $ 1,714 |  |
Accrued Liabilities | 1,500 |  |  |
Loss Contingency, Portion Not Accrued | 31,000 |  |  |
Property insurance program per occurrence limits | 1,000,000 |  |  |
Per occurrence limit for NBCR Coverage | 1,000,000 |  |  |
Value of program trigger | $ 200,000 |  |  |
Coinsurance of program trigger | 20.00% |  |  |
Program trigger deductible | 20.00% |  |  |
Per occurrence limit of the earthquake insurance which covers San Francisco and Los Angeles regions | $ 330,000 |  |  |
Annual aggregate limit of the earthquake insurance which covers San Francisco and Los Angeles regions | 330,000 |  |  |
Amount of earthquake insurance provided by IXP, LLC as direct insurer San Francisco and Los Angeles | $ 30,000 |  |  |
Deductible in insurance as a percentage of the value of the affected property, San Francisco and Los Angeles | 5.00% |  |  |
Per Occurrence Limit of Earthquake Insurance Seattle | $ 110,000 |  |  |
Annual Aggregate Limit of Earthquake Insurance Seattle | $ 110,000 |  |  |
Earthquake Deductible Insurance Percentage of Value of the Affected Property Seattle | 2.00% |  |  |
Construction in Progress |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Net Rentable Area (in sf) | ft² | 2,700,000 |  |  |
Number of real estate properties | Real_Estate_Properties | 9 |  |  |
Boston Properties Limited Partnership |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Note receivable, net | $ 3,937 | $ 1,714 |  |
Operating partnership guarantee to cover liabilities of IXP | 20,000 |  |  |
767 Venture, LLC [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Maximum funding obligation | 6,400 |  |  |
Property insurance program per occurrence limits | 1,625,000 |  |  |
Metropolitan Square |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Net Rentable Area (in sf) | ft² |  |  | 657,000 |
Debt Instrument, Unused Borrowing Capacity, Amount |  |  | $ 100,000 |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 12.00% |
Metropolitan Square | Affiliated Entity |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Note receivable, net | 3,900 |  |  |
Metropolitan Square | Scenario, Plan | Affiliated Entity |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Loans and Leases Receivable, Loans in Process |  |  | $ 20,000 |
Metropolitan Square | Metropolitan Square |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Ownership Percentage |  |  | 20.00% |
601 Lexington Avenue |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Coverage For Acts Of Terrorism Under TRIA Covered in Excess of Amount Covered by IXP | 1,350,000 |  |  |
Coverage For Acts Of Terrorism Under TRIA Covered in Excess of Amount Covered by IXP - Property and Terrorism | 750,000 |  |  |
Coverage For Acts Of Terrorism Under TRIA Covered in Excess of Amount Covered by IXP - Terrorism | 600,000 |  |  |
Sum of Coverage Covered by IXP and Excess Coverage for Property and Terrorism | $ 1,750,000 |  |  |
Office and Life Sciences Building [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Number of real estate properties | Real_Estate_Properties | 162 |  |  |
Office and Life Sciences Building [Member] | Construction in Progress |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Number of real estate properties | Real_Estate_Properties | 6 |  |  |
Office and Life Sciences Building [Member] | 290 Binney | Construction in Progress |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Net Rentable Area (in sf) | ft² | 573,000 |  |  | 573,000
Consolidated Entities, Ownership Percentage | 55.00% |  |  |
Leased percentage | 100.00% |  |  | 100.00%
Office and Life Sciences Building [Member] | 250 Binney Street |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Net Rentable Area (in sf) | ft² | 67,000 |  |  |

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