Earnings Per Share / Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Basic Earnings:
Income from continuing operations attributable to the Company (Numerator)									$ 572,606	$ 433,111	$ 618,113
Net income attributable to the Company in Shares / Units (Denominator)									153,471,000	153,089,000	152,201,000
Income from continuing operations attributable to the Company Per Share / Per Unit Amount (in dollars per share / unit)									$ 3.73	$ 2.83	$ 4.06
Discontinued operations attributable to the Company Income (Numerator)											$ 123,641
Discontinued Operations (in shares)											0
Discontinued operations attributable to the Company Per Share / Unit Amount (in dollars per share / unit)											$ 0.81
Net Income Loss Available To the Company's Common Stockholders / Unitholders											$ 741,594
Allocation of undistributed earnings to participating securities											$ (160)
Allocation of undistributed earnings to participating securities (in shares)											0
Allocation of undistributed earnings to participating securities (in shares)											$ 0.00
Net income attributable to the Company Per Share / Unit Amount (in dollars per share / unit)	$ 0.90	$ 1.20	$ 0.52	$ 1.12	$ 1.14	$ 0.83	$ 0.50	$ 0.35	$ 3.73	$ 2.83	$ 4.87
Effect of Dilutive Securities:
Stock Based Compensation and Exchangeable Senior Notes, Income (Numerator)									$ 0	$ 0	$ 0
Stock Based Compensation and Exchangeable Senior Notes, Shares / Units (Denominator)									373,000	219,000	320,000
Stock Based Compensation and Exchangeable Senior Notes Per Share / Unit Amount									$ (0.01)	$ 0.00	$ (0.01)
Diluted Earnings:
Diluted Earnings: Net income, Income (Numerator)									$ 572,606	$ 433,111	$ 741,594
Diluted Earnings: Net income, Shares / Units (Denominator)									153,844,000	153,308,000	152,521,000
Diluted Earnings: Net income, Per Share / Unit Amount (in dollars per share / unit)	0.90	1.20	0.52	1.11	1.14	0.83	0.50	0.35	$ 3.72	$ 2.83	$ 4.86
Boston Properties Limited Partnership [Member]
Redeemable Common Units									17,668,000	17,364,000	16,925,000
Basic Earnings:
Income from continuing operations attributable to the Company (Numerator)									$ 648,748	$ 499,129	$ 700,151
Net income attributable to the Company in Shares / Units (Denominator)									171,139,000	170,453,000	169,126,000
Income from continuing operations attributable to the Company Per Share / Per Unit Amount (in dollars per share / unit)									$ 3.79	$ 2.93	$ 4.14
Discontinued operations attributable to the Company Income (Numerator)											$ 141,365
Discontinued Operations (in shares)											0
Discontinued operations attributable to the Company Per Share / Unit Amount (in dollars per share / unit)											$ 0.84
Net Income Loss Available To the Company's Common Stockholders / Unitholders											$ 841,338
Allocation of undistributed earnings to participating securities											$ (178)
Allocation of undistributed earnings to participating securities (in shares)											0
Allocation of undistributed earnings to participating securities (in shares)											$ (0.01)
Net income attributable to the Company Per Share / Unit Amount (in dollars per share / unit)	0.92	1.21	0.53	1.13	1.20	0.85	0.51	0.37	$ 3.79	$ 2.93	$ 4.97
Effect of Dilutive Securities:
Stock Based Compensation and Exchangeable Senior Notes, Income (Numerator)									$ 0	$ 0	$ 0
Stock Based Compensation and Exchangeable Senior Notes, Shares / Units (Denominator)									373,000	219,000	320,000
Stock Based Compensation and Exchangeable Senior Notes Per Share / Unit Amount									$ (0.01)	$ (0.01)	$ 0.00
Diluted Earnings:
Diluted Earnings: Net income, Income (Numerator)									$ 648,748	$ 499,129	$ 841,338
Diluted Earnings: Net income, Shares / Units (Denominator)									171,512,000	170,672,000	169,446,000
Diluted Earnings: Net income, Per Share / Unit Amount (in dollars per share / unit)	$ 0.92	$ 1.21	$ 0.53	$ 1.12	$ 1.20	$ 0.85	$ 0.51	$ 0.37	$ 3.78	$ 2.92	$ 4.97