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v3.25.4

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 |  |  |  |

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