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Unsecured Senior Notes (Narrative) (Details) - USD ($) $ in Thousands				9 Months Ended
	Aug. 26, 2024	Feb. 01, 2024	Oct. 26, 2023	Sep. 30, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Proceeds from Secured Notes Payable			$ 600,000
Repayments of Unsecured Debt				$ 700,000	$ 500,000
Proceeds from unsecured senior notes				849,671	747,727
Boston Properties Limited Partnership
Debt Instrument [Line Items]
Repayments of Unsecured Debt				700,000	500,000
Proceeds from unsecured senior notes				849,671	$ 747,727
Senior Notes | Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt				10,700,000
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
Five point Eight Four Two Percent | Senior Notes | Boston Properties Limited Partnership
Debt Instrument [Line Items]
Debt	$ 850,000			$ 850,000
Debt Instrument, Interest Rate, Stated Percentage	5.75%			5.75%
Debt Instrument, Interest Rate, Effective Percentage	5.842%			5.842%
Senior Notes Pricing	99.961%
Proceeds from unsecured senior notes	$ 841,900

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