Consolidated Statements of Capital and Noncontrolling Interests - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Common Stock, Shares, Outstanding	154,563,130		154,563,130			154,458,478
Cumulative effect of a change in accounting principle			$ (4,379,000)	$ 5,496,000
Effective portion of interest rate contracts	$ (4,426,000)		(7,054,000)
Amortization of interest rate contracts	1,666,000	$ 1,666,000	3,332,000	3,332,000
Acquisition of noncontrolling interest in property partnerships	(187,006,000)		(187,006,000)
Contributions from noncontrolling interests in property partnerships	(7,761,000)	(12,265,000)	12,148,000	27,532,000
Distributions to noncontrolling interests in property partnerships	(15,273,000)	$ (13,343,000)	(39,401,000)	(44,033,000)
Boston Properties Limited Partnership
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	2,324,238,000		2,324,238,000			$ 2,000,591,000
Beginning Balance			5,912,323,000
Contributions from noncontrolling interests in property partnerships			12,148,000	$ 27,532,000
Ending Balance	$ 5,401,414,000		$ 5,401,414,000
General Partner [Member]
Common Stock, Shares, Outstanding	1,726,000	1,722,000	1,726,000	1,722,000	1,725,000	1,722,000	1,722,000	1,720,000
Contributions, units	1,000	0	3,000	1,000
Conversion of redeemable partnership units	0	0	1,000	1,000
Limited Partner [Member]
Common Stock, Shares, Outstanding	152,837,000	152,689,000	152,837,000	152,689,000	152,790,000	152,736,000	152,640,000	152,606,000
Contributions, units	26,000	39,000	67,000	50,000
Conversion of redeemable partnership units	21,000	10,000	34,000	33,000
Partners' Capital (General and Limited Partners) [Member]
Beginning Balance	$ 3,603,174,000	$ 3,842,862,000	$ 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	882,000	233,000	5,702,000	1,685,000
Allocated net income for the year	166,687,000	131,082,000	268,470,000	314,182,000
Distributions	(146,835,000)	(123,529,000)	(293,625,000)	(249,644,000)
Unearned compensation	613,000	552,000	(775,000)	(656,000)
Conversion of redeemable partnership units	720,000	364,000	1,212,000	1,196,000
Adjustment to reflect redeemable partnership units at redemption value	100,174,000	(30,791,000)	(306,701,000)	84,641,000
Acquisition of noncontrolling interest in property partnerships	(162,505,000)		(162,505,000)
Ending Balance	3,562,910,000	3,820,773,000	3,562,910,000	3,820,773,000
Preferred Units [Member]
Beginning Balance	193,623,000	193,623,000	193,623,000	193,623,000
Allocated net income for the year	2,625,000	2,625,000	5,250,000	2,625,000
Distributions	(2,625,000)	(2,625,000)	(5,250,000)	(2,625,000)
Ending Balance	193,623,000	193,623,000	193,623,000	193,623,000
Accumulated Other Comprehensive (Income) Loss [Member]
Beginning Balance	(48,734,000)	(49,062,000)	(47,741,000)	(50,429,000)
Effective portion of interest rate contracts	(3,973,000)		(6,332,000)
Amortization of interest rate contracts	1,367,000	1,367,000	2,733,000	2,734,000
Ending Balance	(51,340,000)	(47,695,000)	(51,340,000)	(47,695,000)
Noncontrolling interest - property partnerships [Member]
Beginning Balance	1,710,608,000	1,685,715,000	1,711,445,000	1,683,760,000
Cumulative effect of a change in accounting principle	0		(70,000)
Allocated net income for the year	17,482,000	14,400,000	36,312,000	31,634,000
Amortization of interest rate contracts	144,000	144,000	288,000	288,000
Acquisition of noncontrolling interest in property partnerships	(24,501,000)		(24,501,000)
Contributions from noncontrolling interests in property partnerships	(7,761,000)	(12,265,000)	12,148,000	27,532,000
Distributions to noncontrolling interests in property partnerships	(15,273,000)	(13,343,000)	39,401,000	(44,033,000)
Ending Balance	1,696,221,000	1,699,181,000	1,696,221,000	1,699,181,000
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership
Cumulative effect of a change in accounting principle			(70,000)
Total Capital [Member]
Beginning Balance	5,458,671,000	5,673,138,000	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	882,000	233,000	5,702,000	1,685,000
Allocated net income for the year	186,794,000	148,107,000	310,032,000	348,441,000
Distributions	(149,460,000)	(126,154,000)	(298,875,000)	(252,269,000)
Unearned compensation	613,000	552,000	(775,000)	(656,000)
Conversion of redeemable partnership units	720,000	364,000	1,212,000	1,196,000
Adjustment to reflect redeemable partnership units at redemption value	100,174,000	(30,791,000)	(306,701,000)	84,641,000
Effective portion of interest rate contracts	(3,973,000)		(6,332,000)
Amortization of interest rate contracts	1,511,000	1,511,000	3,021,000	3,022,000
Acquisition of noncontrolling interest in property partnerships	(187,006,000)
Contributions from noncontrolling interests in property partnerships	(7,761,000)	(12,265,000)	12,148,000	(27,532,000)
Distributions to noncontrolling interests in property partnerships	(15,273,000)	(13,343,000)	(39,401,000)	(44,033,000)
Ending Balance	5,401,414,000	5,665,882,000	5,401,414,000	5,665,882,000
Noncontrolling interest - Redeemable partnership units [Member]
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	2,324,238,000	2,235,432,000	2,324,238,000	2,235,432,000	$ 2,414,240,000	$ 2,000,591,000	$ 2,196,603,000	$ 2,292,263,000
Cumulative effect of a change in accounting principle	0	0	(445,000)	563,000
Contributions, value	1,082,000	715,000	35,482,000	34,973,000
Allocated net income for the year	19,028,000	14,879,000	30,627,000	35,311,000
Distributions	(17,206,000)	(14,357,000)	(34,391,000)	(28,708,000)
Unearned compensation	8,286,000	7,010,000	(12,704,000)	(13,443,000)
Conversion of redeemable partnership units	(720,000)	(364,000)	(1,212,000)	(1,196,000)
Adjustment to reflect redeemable partnership units at redemption value	(100,174,000)	30,791,000	306,701,000	(84,641,000)
Effective portion of interest rate contracts	453,000		722,000
Amortization of interest rate contracts	$ 155,000	$ 155,000	$ 311,000	$ 310,000