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v3.23.3

Unsecured Senior Notes (Narrative) (Details) - USD ($) $ in Thousands |  |  | 9 Months Ended
--- | --- | --- | ---
Sep. 01, 2023 | May 15, 2023 | Sep. 30, 2023 | Sep. 30, 2022
Debt Instrument [Line Items] |  |  |  |  |
Proceeds from unsecured senior notes |  |  | $ 747,727 |  | $ 0
Repayments of Unsecured Debt |  |  | 500,000 |  | 0
Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Proceeds from unsecured senior notes |  |  | 747,727 |  | 0
Repayments of Unsecured Debt |  |  | 500,000 |  | $ 0
Senior Notes | Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  |  | $ 10,550,000 |  |
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 |  |  | 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 September 30, 2023, BPLP was in compliance with each of these financial restrictions and requirements. |  |
6.619% unsecured senior notes | Senior Notes | Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt |  | $ 750,000 | $ 750,000 |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 6.50% | 6.50% |  |
Senior Notes Pricing |  | 99.697% |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 6.619% | 6.619% | [1] |
Proceeds from unsecured senior notes |  | $ 741,300 |  |  |
3.279% unsecured senior notes | Senior Notes | Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt | $ 500,000 |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.125% |  |  |  |
Repayments of Unsecured Debt | $ 507,800 |  |  |  |
Debt Instrument, Increase, Accrued Interest | $ 7,800 |  |  |  |
[1] | Yield on issuance date including the effects of discounts on the notes, settlements of interest rate contracts and the amortization of financing costs.

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