Consolidated Statement of Capital and Noncontrolling Interests - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Common Stock, Shares, Outstanding	156,135,959		156,135,959			155,718,825
Effective portion of interest rate contracts	$ 654	$ (659)	$ (4,394)	$ (10,379)
Amortization of interest rate contracts	1,676	1,677	3,352	3,343
Contributions from noncontrolling interests in property partnerships	2,139	2,081	2,420	5,957
Distributions to noncontrolling interests in property partnerships	(19,704)	(13,315)	(37,929)	(29,065)
Preferred Stock Redemption Charge	0	0	(6,412)	0
Net activity from stock option and incentive plan, value	$ 12,897	$ 10,225	$ 51,364	$ 33,285
Accounting Standards Update 2018-09
Accounting Standards Update [Extensible List]				Accounting Standards Update 2018-09
General Partner [Member]
Common Stock, Shares, Outstanding	1,737,000	1,731,000	1,737,000	1,731,000	1,737,000	1,731,000	1,731,000	1,727,000
Net activity from stock option and incentive plan, shares			4,000	1,000
Conversion of redeemable partnership units			2,000	3,000
Limited Partner [Member]
Common Stock, Shares, Outstanding	154,399,000	153,891,000	154,399,000	153,891,000	154,338,000	153,988,000	153,584,000	153,063,000
Net activity from stock option and incentive plan, shares	2,000	5,000	235,000	68,000
Conversion of redeemable partnership units	59,000	302,000	176,000	760,000
Partners' Capital (General and Limited Partners)[Member]
Beginning Balance	$ 4,132,880	$ 4,828,066	$ 4,132,880	$ 4,828,066	$ 4,392,624	$ 4,554,639	$ 4,626,627	$ 3,380,175
Contributions, value	(294)		20,195	8,581
Allocated net income for the period	113,508	271,989	214,609	780,783
Distributions	(153,013)	(152,507)	(305,966)	(304,715)
Conversion of redeemable partnership units, value	2,087	10,849	6,285	26,344
Adjustment to reflect redeemable partnership units at redemption value	(222,032)	70,235	(350,470)	938,403
Preferred Stock Redemption Charge			(6,412)
Net activity from stock option and incentive plan, value		873
Partners' Capital (General and Limited Partners)[Member] | Cumulative Effect, Period of Adoption, Adjustment
Beginning Balance								(1,505)
Preferred Units [Member]
Beginning Balance	0	193,623	0	193,623	0	193,623	193,623	193,623
Allocated net income for the period		2,625	2,560	5,250
Distributions		(2,625)	(2,560)	(5,250)
Preferred Units [Member] | Boston Properties Limited Partnership
Preferred Stock, Redemption Amount	(193,623)		(193,623)
Accumulated Other Comprehensive Loss [Member]
Beginning Balance	(43,166)	(54,921)	(43,166)	(54,921)	(45,139)	(49,890)	(55,700)	(48,335)
Effective portion of interest rate contracts	593	(601)	3,962	(9,333)
Amortization of interest rate contracts	1,380	1,380	2,762	2,747
Noncontrolling interest - property partnerships [Member]
Beginning Balance	1,725,343	1,724,588	1,725,343	1,724,588	1,725,600	1,726,933	1,736,445	1,728,689
Allocated net income for the period	17,164	(767)	33,631	18,719
Effective portion of interest rate contracts	0			0
Amortization of interest rate contracts	144	144	288	288
Contributions from noncontrolling interests in property partnerships	2,139	2,081	2,420	5,957
Distributions to noncontrolling interests in property partnerships	(19,704)	(13,315)	(37,929)	(29,065)
Total Capital [Member]
Beginning Balance	5,815,057	6,691,356	5,815,057	6,691,356	6,073,085	6,425,305	6,500,995	5,254,152
Contributions, value	(294)		20,195	8,581
Allocated net income for the period	130,672	273,847	250,800	804,752
Distributions	(153,013)	(155,132)	(308,526)	(309,965)
Conversion of redeemable partnership units, value	2,087	10,849	6,285	26,344
Adjustment to reflect redeemable partnership units at redemption value	(222,032)	70,235	(350,470)	938,403
Effective portion of interest rate contracts	593	(601)	3,962	(9,333)
Amortization of interest rate contracts	1,524	1,524	3,050	3,035
Contributions from noncontrolling interests in property partnerships	2,139	2,081	2,420	5,957
Distributions to noncontrolling interests in property partnerships	(19,704)	(13,315)	(37,929)	(29,065)
Preferred Stock, Redemption Amount	(193,623)		(193,623)
Preferred Stock Redemption Charge			(6,412)
Net activity from stock option and incentive plan, value		873
Total Capital [Member] | Cumulative Effect, Period of Adoption, Adjustment
Beginning Balance								(1,505)
Noncontrolling interest - Redeemable partnership units [Member]
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	2,008,478	1,581,010	2,008,478	1,581,010	$ 1,780,044	$ 1,643,024	$ 1,639,855	2,468,753
Contributions, value	13,191		31,653	25,029
Allocated net income for the period	12,338	29,986	23,422	87,525
Distributions	(17,253)	(17,194)	(34,540)	(34,638)
Conversion of redeemable partnership units, value	(2,087)	(10,849)	(6,285)	(26,344)
Adjustment to reflect redeemable partnership units at redemption value	222,032	(70,235)	350,470	(938,403)
Effective portion of interest rate contracts	61	(58)	432	(1,046)
Amortization of interest rate contracts	152	153	302	308
Contributions from noncontrolling interests in property partnerships	0	0	0	0
Distributions to noncontrolling interests in property partnerships	0	0	0	$ 0
Preferred Stock, Redemption Amount	$ 0		0
Preferred Stock Redemption Charge			0
Net activity from stock option and incentive plan, value		$ 9,352
Noncontrolling interest - Redeemable partnership units [Member] | Cumulative Effect, Period of Adoption, Adjustment
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount								$ (174)
Dividends In Excess Of Earnings [Member]
Preferred Stock Redemption Charge			$ 6,412