Consolidated Statements of Capital and Noncontrolling Interests - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Common Stock, Shares, Outstanding	154,572,073		154,572,073			154,458,478
Cumulative effect of a change in accounting principle			$ (4,379,000)	$ 5,496,000
Effective portion of interest rate contracts	$ (2,253,000)	$ 1,325,000	(9,307,000)	1,325,000
Amortization of interest rate contracts	1,666,000	1,666,000	4,998,000	4,998,000
Acquisition of noncontrolling interest in property partnership	43,000		(186,963,000)
sale of an interest in property partnerships	0		0
Contributions from noncontrolling interests in property partnerships	14,820,000	9,616,000	26,968,000	37,148,000
Distributions to noncontrolling interests in property partnerships	(13,748,000)	$ (12,763,000)	(53,149,000)	(56,796,000)
Boston Properties Limited Partnership
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	2,335,272,000		2,335,272,000			$ 2,000,591,000
Beginning Balance			5,912,323,000
Contributions from noncontrolling interests in property partnerships			26,968,000	$ 37,148,000
Ending Balance	$ 5,367,322,000		$ 5,367,322,000
General Partner [Member]
Common Stock, Shares, Outstanding	1,726,000	1,722,000	1,726,000	1,722,000	1,726,000	1,722,000	1,722,000	1,720,000
Contributions, units	0	0	3,000	1,000
Conversion of redeemable partnership units	0	0	1,000	1,000
Limited Partner [Member]
Common Stock, Shares, Outstanding	152,846,000	152,718,000	152,846,000	152,718,000	152,837,000	152,736,000	152,689,000	152,606,000
Contributions, units	2,000	3,000	69,000	53,000
Conversion of redeemable partnership units	7,000	26,000	41,000	59,000
Partners' Capital (General and Limited Partners) [Member]
Beginning Balance	$ 3,562,910,000	$ 3,820,773,000	$ 4,054,996,000	$ 3,664,436,000
Cumulative effect of a change in accounting principle	0	0	(3,864,000)	4,933,000
Contributions, value	(3,915,000)	354,000	1,787,000	2,039,000
Allocated net income for the period	109,611,000	122,384,000	378,081,000	433,941,000
Distributions	(146,843,000)	(146,718,000)	(440,468,000)	(393,737,000)
Unearned compensation	(7,205,000)	768,000	(7,980,000)	112,000
Conversion of redeemable partnership units	223,000	916,000	1,435,000	2,112,000
Adjustment to reflect redeemable partnership units at redemption value	(9,252,000)	48,622,000	(315,953,000)	133,263,000
Acquisition of noncontrolling interest in property partnership	43,000		(162,462,000)
Ending Balance	3,505,572,000	3,847,099,000	3,505,572,000	3,847,099,000
Preferred Units [Member]
Beginning Balance	193,623,000	193,623,000	193,623,000	193,623,000
Allocated net income for the period	2,625,000	2,625,000	7,875,000	7,875,000
Distributions	(2,625,000)	(2,625,000)	(7,875,000)	(7,875,000)
Ending Balance	193,623,000	193,623,000	193,623,000	193,623,000
Accumulated Other Comprehensive (Income) Loss [Member]
Beginning Balance	(51,340,000)	(47,695,000)	(47,741,000)	(50,429,000)
Effective portion of interest rate contracts	(2,022,000)	1,190,000	(8,354,000)	1,190,000
Amortization of interest rate contracts	1,366,000	1,368,000	4,099,000	4,102,000
Ending Balance	(51,996,000)	(45,137,000)	(51,996,000)	(45,137,000)
Noncontrolling interest - property partnerships [Member]
Beginning Balance	1,696,221,000	1,699,181,000	1,711,445,000	1,683,760,000
Cumulative effect of a change in accounting principle	0		(70,000)
Allocated net income for the period	18,470,000	14,850,000	54,782,000	46,484,000
Effective portion of interest rate contracts				0
Amortization of interest rate contracts	144,000	144,000	432,000	432,000
Acquisition of noncontrolling interest in property partnership			(24,501,000)
sale of an interest in property partnerships	4,216,000		4,216,000
Contributions from noncontrolling interests in property partnerships	14,820,000	9,616,000	26,968,000	37,148,000
Distributions to noncontrolling interests in property partnerships	(13,748,000)	(12,763,000)	(53,149,000)	(56,796,000)
Ending Balance	1,720,123,000	1,711,028,000	1,720,123,000	1,711,028,000
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership
Cumulative effect of a change in accounting principle			(70,000)
Total Capital [Member]
Beginning Balance	5,401,414,000	5,665,882,000	5,912,323,000	5,491,390,000
Cumulative effect of a change in accounting principle	0	0	(3,934,000)	4,933,000
Contributions, value	(3,915,000)	354,000	1,787,000	2,039,000
Allocated net income for the period	130,706,000	139,859,000	440,738,000	488,300,000
Distributions	(149,468,000)	(149,343,000)	(448,343,000)	(401,612,000)
Unearned compensation	(7,205,000)	768,000	(7,980,000)	112,000
Conversion of redeemable partnership units	223,000	916,000	1,435,000	2,112,000
Adjustment to reflect redeemable partnership units at redemption value	(9,252,000)	48,622,000	(315,953,000)	133,263,000
Effective portion of interest rate contracts	(2,022,000)	1,190,000	(8,354,000)	1,190,000
Amortization of interest rate contracts	1,510,000	1,512,000	4,531,000	4,534,000
Acquisition of noncontrolling interest in property partnership	43,000		(186,963,000)
sale of an interest in property partnerships	4,216,000		4,216,000
Contributions from noncontrolling interests in property partnerships	14,820,000	9,616,000	26,968,000	37,148,000
Distributions to noncontrolling interests in property partnerships	(13,748,000)	(12,763,000)	(53,149,000)	(56,796,000)
Ending Balance	5,367,322,000	5,706,613,000	5,367,322,000	5,706,613,000
Noncontrolling interest - Redeemable partnership units [Member]
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	2,335,272,000	2,190,664,000	2,335,272,000	2,190,664,000	$ 2,324,238,000	$ 2,000,591,000	$ 2,235,432,000	$ 2,292,263,000
Cumulative effect of a change in accounting principle	0	0	(445,000)	563,000
Contributions, value	0	(3,000)	35,482,000	34,970,000
Allocated net income for the period	12,506,000	13,817,000	43,133,000	49,128,000
Distributions	(17,200,000)	(17,022,000)	(51,591,000)	(45,730,000)
Unearned compensation	6,774,000	7,689,000	(5,930,000)	(5,754,000)
Conversion of redeemable partnership units	(223,000)	(916,000)	(1,435,000)	(2,112,000)
Adjustment to reflect redeemable partnership units at redemption value	9,252,000	(48,622,000)	315,953,000	(133,263,000)
Effective portion of interest rate contracts	(231,000)	135,000	(953,000)	135,000
Amortization of interest rate contracts	$ 156,000	$ 154,000	$ 467,000	$ 464,000