Commitments And Contingencies (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) ft² Real_Estate_Properties	Dec. 31, 2023 USD ($)	Oct. 02, 2023 USD ($)	Jan. 05, 2023 ft²
Commitments And Contingencies [Line Items]
Letter of credit and performance obligations	$ 21,600
Note receivable, net	2,274	$ 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	3,200,000
Number of real estate properties | Real_Estate_Properties	11
Boston Properties Limited Partnership
Commitments And Contingencies [Line Items]
Note receivable, net	$ 2,274	$ 1,714
Operating partnership guarantee to cover liabilities of IXP	20,000
767 Venture, LLC [Member]
Commitments And Contingencies [Line Items]
Maximum funding obligation	8,500
Property insurance program per occurrence limits	1,625,000
Metropolitan Square
Commitments And Contingencies [Line Items]
Ownership Percentage			20.00%
Metropolitan Square | Affiliated Entity
Commitments And Contingencies [Line Items]
Note receivable, net	2,200
Metropolitan Square | Subordinated Debt
Commitments And Contingencies [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount			$ 100,000
Debt Instrument, Interest Rate, Stated Percentage			12.00%
Metropolitan Square | Scenario, Plan | Subordinated Debt | Affiliated Entity
Commitments And Contingencies [Line Items]
Loans and Leases Receivable, Loans in Process			$ 20,000
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	165
Office and Life Sciences Building [Member] | Construction in Progress
Commitments And Contingencies [Line Items]
Number of real estate properties | Real_Estate_Properties	7
Office and Life Sciences Building [Member] | 290 Binney | Construction in Progress
Commitments And Contingencies [Line Items]
Net Rentable Area (in sf) | ft²	566,000			566,000
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