Interest Coverage - Minimum

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- Definition

Leverage ratio - maximum

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- Definition

Secured debt leverage ratio - maximum

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- Definition

Unencumbered Asset Value - Minimum

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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Increase for accrued, but unpaid interest on the debt instrument for the period.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Unsecured Senior Notes (Narrative) (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 15, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Aug. 26, 2024
Debt Instrument [Line Items]
Repayments of Unsecured Debt		$ 850,000	$ 700,000	$ 500,000
Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt		9,850,000
Repayments of Unsecured Debt		$ 850,000	$ 700,000	$ 500,000
Senior Notes \| Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt Instrument, Covenant Description		The indenture relating to the unsecured senior notes contains certain financial restrictions and requirements, including (1) a leverage ratio not to exceed 60%, (2) a secured debt leverage ratio not to exceed 50%, (3) an interest coverage ratio of greater than 1.50, and (4) an unencumbered asset value of not less than 150% of unsecured debt.
Leverage ratio - maximum		60.00%
Secured debt leverage ratio - maximum		50.00%
Interest Coverage - Minimum		1.50
Unencumbered Asset Value - Minimum		150.00%
Debt Instrument, Covenant Compliance		At December 31, 2025, BPLP was in compliance with each of these financial restrictions and requirements
3.350% unsecured senior notes \| Senior Notes \| Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt	$ 850,000
Debt Instrument, Interest Rate, Stated Percentage	3.20%				5.75%
Repayments of Unsecured Debt	$ 863,600
Debt Instrument, Increase, Accrued Interest	$ 13,600