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Subsequent Events (Details) - USD ($) $ in Thousands				12 Months Ended
	Feb. 14, 2021	Feb. 05, 2021	Feb. 02, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 29, 2021
Subsequent Event [Line Items]
Common stock, shares issued				155,797,725	154,869,198
Repayments of Unsecured Debt				$ 0	$ 699,237	$ 699,517
Boston Properties Limited Partnership
Subsequent Event [Line Items]
Repayments of Unsecured Debt				0	$ 699,237	$ 699,517
Boston Properties Limited Partnership | Senior Notes
Subsequent Event [Line Items]
Debt				9,700,000
Boston Properties Limited Partnership | 4.289% unsecured senior notes | Senior Notes
Subsequent Event [Line Items]
Debt				$ 850,000
Debt Instrument, Interest Rate, Stated Percentage				4.125%
Restricted Stock [Member]
Subsequent Event [Line Items]
Common stock, shares issued				29,630	26,503	20,320
LTIP Units [Member] | Boston Properties Limited Partnership
Subsequent Event [Line Items]
Number of shares issued				207,181	181,919	205,838
Subsequent Event [Member] | Boston Properties Limited Partnership | 4.289% unsecured senior notes | Senior Notes
Subsequent Event [Line Items]
Debt	$ 850,000
Debt Instrument, Interest Rate, Stated Percentage	4.125%
Repayments of Unsecured Debt	$ 858,700
Debt Instrument, Increase, Accrued Interest	$ 8,700
Subsequent Event [Member] | Restricted Stock [Member]
Subsequent Event [Line Items]
Common stock, shares issued							33,449
Subsequent Event [Member] | LTIP Units [Member] | Boston Properties Limited Partnership
Subsequent Event [Line Items]
Number of shares issued			263,527
Subsequent Event [Member] | MYLTIP 2021
Subsequent Event [Line Items]
Value of MYLTIP Awards			$ 15,300
Minimum earned awards			0
Maximum Earned Awards			352,021
Earned awards - Target			176,009
Subsequent Event [Member] | MYLTIP 2018
Subsequent Event [Line Items]
Value of MYLTIP Awards		$ 4,600
Forfeitures, in units		285,925
Final awards percentage of target		29.20%

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