Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company	$ 104,299	$ 222,989	$ 182,215	$ 366,044
Noncontrolling interest-common units of the Operating Partnership	(12,117)	(25,708)	(21,169)	(42,061)
Noncontrolling interest in property partnerships	(19,768)	(18,546)	(38,428)	(36,095)
Interest expense	(142,473)	(104,142)	(276,680)	(205,370)
Company's share of net operating income from joint ventures	(503,489)	(484,042)	(994,495)	(953,358)
Depreciation and amortization expense	(202,577)	(183,146)	(411,311)	(360,770)
Transaction costs	(308)	(496)	(1,219)	(496)
General and administrative expense	(44,175)	(34,665)	(99,977)	(77,859)
Unrealized Gain (Loss) on Investments	(124)	0	(383)	0
Gains (losses) from investments in securities	(1,571)	4,716	(3,236)	6,978
Interest and other income (loss)	(17,343)	(1,195)	(28,284)	(2,423)
Gains on sales of real estate	0	(96,247)	0	(118,948)
Income (loss) from unconsolidated joint ventures	6,668	54	14,237	(2,135)
Other Income - assignment fee	0	(6,624)	0	(6,624)
Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company	104,299	222,989	182,215	366,044
Noncontrolling interest-common units of the Operating Partnership	12,117	25,708	21,169	42,061
Noncontrolling interest in property partnerships	19,768	18,546	38,428	36,095
Interest expense	142,473	104,142	276,680	205,370
Depreciation and amortization expense	202,577	183,146	411,311	360,770
Transaction costs	308	496	1,219	496
Operating expense	4,609	3,239	9,844	7,304
General and administrative expense	44,175	34,665	99,977	77,859
Unrealized Gain (Loss) on Investments	124	0	383	0
Gains (losses) from investments in securities	1,571	(4,716)	3,236	(6,978)
Interest and other income (loss)	17,343	1,195	28,284	2,423
Gains on sales of real estate	0	96,247	0	118,948
Income (loss) from unconsolidated joint ventures	(6,668)	(54)	(14,237)	2,135
Other Income - assignment fee	0	6,624	0	6,624
Other revenue	4,609	3,239	9,844	7,304
Company's share of Net Operating Income	497,785	471,890	982,450	931,472
Unconsolidated Joint Ventures [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense	(58,799)	(32,219)	(116,049)	(62,592)
Depreciation and amortization expense	(51,233)	(43,293)	(101,211)	(87,957)
Transaction costs	(27)	(811)	(101)	(811)
Income (loss) from unconsolidated joint ventures	6,668	54	14,237	(2,135)
Unconsolidated Joint Ventures [Member] | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Company's share of net operating income from joint ventures	42,254	35,710	83,010	73,031
Boston Properties Limited Partnership
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company	118,098	253,788	206,928	415,617
Noncontrolling interest in property partnerships	(19,768)	(18,546)	(38,428)	(36,095)
Interest expense	(142,473)	(104,142)	(276,680)	(205,370)
Depreciation and amortization expense	(200,895)	(181,416)	(407,767)	(357,302)
Transaction costs	(308)	(496)	(1,219)	(496)
General and administrative expense	(44,175)	(34,665)	(99,977)	(77,859)
Unrealized Gain (Loss) on Investments	(124)	0	(383)	0
Gains (losses) from investments in securities	(1,571)	4,716	(3,236)	6,978
Interest and other income (loss)	(17,343)	(1,195)	(28,284)	(2,423)
Gains on sales of real estate	0	(99,608)	0	(122,992)
Income (loss) from unconsolidated joint ventures	6,668	54	14,237	(2,135)
Other Income - assignment fee	0	(6,624)	0	(6,624)
Boston Properties Limited Partnership | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the Company	118,098	253,788	206,928	415,617
Noncontrolling interest in property partnerships	19,768	18,546	38,428	36,095
Interest expense	142,473	104,142	276,680	205,370
Depreciation and amortization expense	200,895	181,416	407,767	357,302
Transaction costs	308	496	1,219	496
Operating expense	4,609	3,239	9,844	7,304
General and administrative expense	44,175	34,665	99,977	77,859
Unrealized Gain (Loss) on Investments	124	0	383	0
Gains (losses) from investments in securities	1,571	(4,716)	3,236	(6,978)
Interest and other income (loss)	17,343	1,195	28,284	2,423
Gains on sales of real estate	0	99,608	0	122,992
Income (loss) from unconsolidated joint ventures	(6,668)	(54)	(14,237)	2,135
Other Income - assignment fee	0	6,624	0	6,624
Other revenue	4,609	3,239	9,844	7,304
Company's share of Net Operating Income	497,785	471,890	982,450	931,472
Management Service [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	(9,858)	(6,354)	(18,838)	(12,185)
Management Service [Member] | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	9,858	6,354	18,838	12,185
Management Service [Member] | Boston Properties Limited Partnership
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	(9,858)	(6,354)	(18,838)	(12,185)
Management Service [Member] | Boston Properties Limited Partnership | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	9,858	6,354	18,838	12,185
Noncontrolling interest - property partnerships [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Company's share of net operating income from joint ventures	47,958	47,862	95,055	94,917
Noncontrolling interest - property partnerships [Member] | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Company's share of net operating income from joint ventures	47,958	47,862	95,055	94,917
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Company's share of net operating income from joint ventures	$ 47,958	$ 47,862	$ 95,055	$ 94,917