Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Development and management services income	$ 22,554	$ 25,316	$ 29,695
Income from unconsolidated joint ventures	22,770	12,769	75,074
Gains on consolidation of joint ventures	0	0	385,991
Interest and other income	6,777	8,765	8,310
Gains (losses) from investments in securities	(653)	1,038	2,911
Gains (losses) from early extinguishments of debt	(22,040)	(10,633)	122
Income from discontinued operations	0	0	8,022
Gain on sale of real estate from discontinued operations	0	0	112,829
Gain on forgiveness of debt from discontinued operations	0	0	20,182
General and administrative expense	96,319	98,937	115,329
Transaction costs	1,259	3,140	1,744
Depreciation and amortization expense	639,542	628,573	560,637
Interest expense	432,196	455,743	446,880
Impairment loss	0	0	8,306
Impairment loss from discontinued operations	0	0	3,241
Noncontrolling interest in property partnerships	149,855	30,561	1,347
Noncontrolling interest - redeemable preferred units	6	1,023	6,046
Noncontrolling interest-common units of the Operating Partnership	66,951	50,862	70,085
Noncontrolling interest in discontinued operations-common units of the Operating Partnership	0	0	14,151
Preferred dividends / distributions	10,500	10,500	8,057
Net income attributable to the Company''s common shareholders / unitholders	572,606	433,111	741,754
Business Intersegment, Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Operating Income	1,563,931	1,507,156	1,334,441
Development and management services income	22,554	25,316	29,695
Income from unconsolidated joint ventures	22,770	12,769	75,074
Gains on consolidation of joint ventures	0	0	385,991
Interest and other income	6,777	8,765	8,310
Gains (losses) from investments in securities	(653)	1,038	2,911
Gains (losses) from early extinguishments of debt	(22,040)	(10,633)	122
Income from discontinued operations	0	0	8,022
Gain on sale of real estate from discontinued operations	0	0	112,829
Gain on forgiveness of debt from discontinued operations	0	0	20,182
Gains on sales of real estate	375,895	168,039	0
General and administrative expense	96,319	98,937	115,329
Transaction costs	1,259	3,140	1,744
Depreciation and amortization expense	639,542	628,573	560,637
Interest expense	432,196	455,743	446,880
Impairment loss	0	0	8,306
Impairment loss from discontinued operations	0	0	3,241
Noncontrolling interest in property partnerships	149,855	30,561	1,347
Noncontrolling interest - redeemable preferred units	6	1,023	6,046
Noncontrolling interest-common units of the Operating Partnership	66,951	50,862	70,085
Noncontrolling interest in discontinued operations-common units of the Operating Partnership	0	0	14,151
Preferred dividends / distributions	10,500	10,500	8,057
Net income attributable to the Company''s common shareholders / unitholders	572,606	433,111	741,754
Boston Properties Limited Partnership [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Development and management services income	22,554	25,316	29,695
Income from unconsolidated joint ventures	22,770	12,769	75,074
Gains on consolidation of joint ventures	0	0	385,991
Interest and other income	6,777	8,765	8,310
Gains (losses) from investments in securities	(653)	1,038	2,911
Gains (losses) from early extinguishments of debt	(22,040)	(10,633)	122
Income from discontinued operations	0	0	8,022
Gain on sale of real estate from discontinued operations	0	0	115,459
Gain on forgiveness of debt from discontinued operations	0	0	20,736
General and administrative expense	96,319	98,937	115,329
Transaction costs	1,259	3,140	1,744
Depreciation and amortization expense	631,549	620,064	552,589
Interest expense	432,196	455,743	446,880
Impairment loss	0	0	4,401
Impairment loss from discontinued operations	0	0	2,852
Noncontrolling interest in property partnerships	149,855	30,561	1,347
Noncontrolling interest - redeemable preferred units	6	1,023	6,046
Preferred dividends / distributions	10,500	10,500	8,057
Net income attributable to the Company''s common shareholders / unitholders	648,748	499,129	841,516
Boston Properties Limited Partnership [Member] | Business Intersegment, Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net Operating Income	1,563,931	1,507,156	1,334,441
Development and management services income	22,554	25,316	29,695
Income from unconsolidated joint ventures	22,770	12,769	75,074
Gains on consolidation of joint ventures	0	0	385,991
Interest and other income	6,777	8,765	8,310
Gains (losses) from investments in securities	(653)	1,038	2,911
Gains (losses) from early extinguishments of debt	(22,040)	(10,633)	122
Income from discontinued operations	0	0	8,022
Gain on sale of real estate from discontinued operations	0	0	115,459
Gain on forgiveness of debt from discontinued operations	0	0	20,736
Gains on sales of real estate	377,093	174,686	0
General and administrative expense	96,319	98,937	115,329
Transaction costs	1,259	3,140	1,744
Depreciation and amortization expense	631,549	620,064	552,589
Interest expense	432,196	455,743	446,880
Impairment loss	0	0	4,401
Impairment loss from discontinued operations	0	0	2,852
Noncontrolling interest in property partnerships	149,855	30,561	1,347
Noncontrolling interest - redeemable preferred units	6	1,023	6,046
Preferred dividends / distributions	10,500	10,500	8,057
Net income attributable to the Company''s common shareholders / unitholders	$ 648,748	$ 499,129	$ 841,516