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Unsecured Senior Notes (Narrative) (Details) - USD ($) $ in Thousands					12 Months Ended
	Dec. 31, 2024		Aug. 26, 2024	Feb. 01, 2024	Dec. 31, 2024		Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Repayments of Unsecured Debt					$ 700,000		$ 500,000	$ 0
Proceeds from unsecured senior notes					849,671		747,727	749,557
Boston Properties Limited Partnership
Debt Instrument [Line Items]
Repayments of Unsecured Debt					700,000		500,000	0
Proceeds from unsecured senior notes					849,671		$ 747,727	$ 749,557
Senior Notes | Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt	$ 10,700,000				$ 10,700,000
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%				60.00%
Secured debt leverage ratio - maximum	50.00%				50.00%
Interest Coverage - Minimum	1.50				1.50
Unencumbered Asset Value - Minimum	150.00%				150.00%
Debt Instrument, Covenant Compliance	At December 31, 2024, BPLP was in compliance with each of these financial restrictions and requirements.
3.916% unsecured senior notes | Senior Notes | Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt				$ 700,000
Debt Instrument, Interest Rate, Stated Percentage				3.80%
Repayments of Unsecured Debt				$ 713,300
Debt Instrument, Increase, Accrued Interest				$ 13,300
5.842% unsecured senior notes | Senior Notes | Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt	$ 850,000		$ 850,000		$ 850,000
Debt Instrument, Interest Rate, Stated Percentage	5.75%		5.75%		5.75%
Senior Notes Pricing			99.961%
Debt Instrument, Interest Rate, Effective Percentage	5.842%	[1]	5.842%		5.842%	[1]
Proceeds from unsecured senior notes			$ 841,900
[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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