Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company's common shareholders / unitholders	$ 117,337	$ 76,753	$ 348,086	$ 355,114
Preferred Stock Dividends / Distributions	(2,625)	(2,589)	(7,875)	(7,796)
Noncontrolling interest-common units of the Operating Partnership	(13,402)	(9,387)	(40,350)	(42,120)
Noncontrolling interest in property partnerships	(14,340)	17,225	(33,967)	(53)
Interest expense	(92,032)	(104,641)	(282,709)	(314,953)
Losses from interest rate contracts	0	(140)	0	(140)
Depreciation and amortization expense	(152,164)	(203,748)	(463,288)	(516,371)
Impairment of Real Estate	0	(1,783)	0	(1,783)
Transaction costs	(239)	(249)	(572)	(1,187)
General and administrative expense	(25,792)	(25,165)	(84,319)	(79,936)
Gains (losses) from early extinguishments of debt	0	371	(14,354)	371
Gains from investments in securities	(944)	(976)	(2,716)	(1,713)
Interest and other income	(1,329)	(3,628)	(3,447)	(6,657)
Income from unconsolidated joint ventures	(843)	(1,464)	(7,035)	(5,489)
Development and management services income	(10,811)	(6,364)	(24,648)	(18,586)
Business Intersegment, Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company's common shareholders / unitholders	117,337	76,753	348,086	355,114
Preferred Stock Dividends / Distributions	2,625	2,589	7,875	7,796
Noncontrolling interest-common units of the Operating Partnership	13,402	9,387	40,350	42,120
Noncontrolling interest in property partnerships	14,340	(17,225)	33,967	53
Interest expense	92,032	104,641	282,709	314,953
Losses from interest rate contracts	0	140	0	140
Depreciation and amortization expense	152,164	203,748	463,288	516,371
Impairment of Real Estate	0	1,783	0	1,783
Transaction costs	239	249	572	1,187
General and administrative expense	25,792	25,165	84,319	79,936
Gains on sales of real estate	2,891	12,983	6,791	80,606
Gains (losses) from early extinguishments of debt	0	(371)	14,354	(371)
Gains from investments in securities	944	976	2,716	1,713
Interest and other income	1,329	3,628	3,447	6,657
Income from unconsolidated joint ventures	843	1,464	7,035	5,489
Development and management services income	10,811	6,364	24,648	18,586
Net Operating Income	401,113	382,186	1,202,175	1,206,773
Boston Properties Limited Partnership
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company's common shareholders / unitholders	132,693	91,306	395,199	408,540
Preferred Stock Dividends / Distributions	(2,625)	(2,589)	(7,875)	(7,796)
Noncontrolling interest in property partnerships	(14,340)	17,225	(33,967)	(53)
Interest expense	(92,032)	(104,641)	(282,709)	(314,953)
Losses from interest rate contracts	0	(140)	0	(140)
Depreciation and amortization expense	(150,210)	(198,582)	(457,102)	(507,234)
Impairment of Real Estate	0	(1,783)	0	(1,783)
Transaction costs	(239)	(249)	(572)	(1,187)
General and administrative expense	(25,792)	(25,165)	(84,319)	(79,936)
Gains (losses) from early extinguishments of debt	0	371	(14,354)	371
Gains from investments in securities	(944)	(976)	(2,716)	(1,713)
Interest and other income	(1,329)	(3,628)	(3,447)	(6,657)
Income from unconsolidated joint ventures	(843)	(1,464)	(7,035)	(5,489)
Development and management services income	(10,811)	(6,364)	(24,648)	(18,586)
Boston Properties Limited Partnership | Business Intersegment, Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company's common shareholders / unitholders	132,693	91,306	395,199	408,540
Preferred Stock Dividends / Distributions	2,625	2,589	7,875	7,796
Noncontrolling interest in property partnerships	14,340	(17,225)	33,967	53
Interest expense	92,032	104,641	282,709	314,953
Losses from interest rate contracts	0	140	0	140
Depreciation and amortization expense	150,210	198,582	457,102	507,234
Impairment of Real Estate	0	1,783	0	1,783
Transaction costs	239	249	572	1,187
General and administrative expense	25,792	25,165	84,319	79,936
Gains on sales of real estate	2,891	12,983	7,368	82,775
Gains (losses) from early extinguishments of debt	0	(371)	14,354	(371)
Gains from investments in securities	944	976	2,716	1,713
Interest and other income	1,329	3,628	3,447	6,657
Income from unconsolidated joint ventures	843	1,464	7,035	5,489
Development and management services income	10,811	6,364	24,648	18,586
Net Operating Income	$ 401,113	$ 382,186	$ 1,202,175	$ 1,206,773