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Commitments And Contingencies (Details) $ in Thousands |  |  |  |  | 10 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 17, 2025 USD ($) | Oct. 16, 2025 USD ($) | Jan. 24, 2025 | Dec. 09, 2024 USD ($) | Dec. 15, 2025 | Dec. 31, 2025 USD ($) ft² | Oct. 02, 2023 USD ($) ft² | Jan. 05, 2023 ft² | Dec. 31, 2019 USD ($)
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Letter of credit and performance obligations |  |  |  |  |  | $ 23,200 |  |  |
Accrued Liabilities |  |  |  | $ 2,200 |  |  |  |  | $ 1,500
Payments for Legal Settlements |  |  |  | $ 2,700 |  |  |  |  |
Loss Contingency, Portion Not Accrued |  |  |  |  |  | 25,000 |  |  |
Loss Contingency, Number of Defendants |  |  | 90 |  | 85 |  |  |  |
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 |  |  |  |  |  | 3,500,000 |  |  |
Boston Properties Limited Partnership |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Operating partnership guarantee to cover liabilities of IXP |  |  |  |  |  | $ 20,000 |  |  |
767 Venture, LLC [Member] |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Property insurance program per occurrence limits |  |  |  |  |  | $ 1,625,000 |  |  |
3 Hudson Boulevard [Member] |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  | 2,000,000.0 |  |  |
Ownership Percentage |  |  |  |  |  | 25.00% |  |  |
3 Hudson Boulevard [Member] | Notes Receivables [Member] | Unconsolidated Properties | Related Party |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Related party note receivable, net |  | $ 80,000 |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 7.25% | 3.61% |  |  |  |  |  |  |
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 |  |  |  |  |  | $ 9,400 |  |  |
Metropolitan Square | Scenario, Plan | Affiliated Entity |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Other Commitment |  |  |  |  |  |  | $ 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 |  |  |
3 Hudson Boulevard [Member] | Unconsolidated Properties |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 3.61% |  |  |  |  |  |  |
3 Hudson Boulevard [Member] | Affiliated Entity |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Note receivable, net |  |  |  |  |  | $ 18,400 |  |  |
3 Hudson Boulevard [Member] | Scenario, Plan | Affiliated Entity |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Other Commitment | $ 50,000 |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 7.25% |  |  |  |  |  |  |  |
Office Building [Member] |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  | 409,200 |  |  |
Office Building [Member] | 290 Binney Street | Construction in Progress |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  |  | 573,000 |
Consolidated Entities, Ownership Percentage |  |  |  |  |  | 55.00% |  |  |
Leased percentage |  |  |  |  |  |  |  | 100.00% |
Office Building [Member] | 250 Binney Street |  |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  | 67,000 |  |  |

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- Definition The amount of cash paid for the settlement of litigation or for other legal issues during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (g) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-25 + Details
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