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Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($)		3 Months Ended		12 Months Ended
	Dec. 19, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the company's common shareholders / unitholders		$ 111,882,000	$ 184,537,000	$ 848,947,000	$ 496,223,000	$ 862,227,000
Preferred Stock Redemption Charge				0	(6,412,000)	0
Preferred dividends / distributions				0	(2,560,000)	(10,500,000)
Noncontrolling interest-common units of the Operating Partnership				(96,780,000)	(55,931,000)	(97,704,000)
Noncontrolling interest in property partnerships				(74,857,000)	(70,806,000)	(48,260,000)
Interest expense				(437,139,000)	(423,346,000)	(431,717,000)
Losses from early extinguishment of debt				0	45,182,000	0
Unrealized Gain (Loss) on Investments				150,000	0	0
Company's share of net operating income from joint ventures				(1,929,527,000)	(1,814,288,000)	(1,694,075,000)
Loss from unconsolidated joint ventures				59,840,000	2,570,000	85,110,000
Depreciation and amortization expense				(749,775,000)	(717,336,000)	(683,751,000)
Transaction costs				(2,905,000)	(5,036,000)	(1,531,000)
General and administrative expense				(146,378,000)	(151,573,000)	(133,112,000)
Gains (losses) from investments in securities				6,453,000	(5,626,000)	(5,261,000)
Other Income - assignment fee				(6,624,000)	0	0
Interest and other income (loss)				(11,940,000)	(5,704,000)	(5,953,000)
Sales-type and Direct Financing Leases, Profit (Loss)	$ (10,100,000)			(10,058,000)	0	0
Gains on sales of real estate				(437,019,000)	(123,660,000)	(618,982,000)
Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the company's common shareholders / unitholders				848,947,000	496,223,000	862,227,000
Preferred Stock Redemption Charge				0	6,412,000	0
Preferred dividends / distributions				0	2,560,000	10,500,000
Noncontrolling interest-common units of the Operating Partnership				96,780,000	55,931,000	97,704,000
Noncontrolling interest in property partnerships				74,857,000	70,806,000	48,260,000
Interest expense				437,139,000	423,346,000	431,717,000
Losses from early extinguishment of debt				0	45,182,000	0
Unrealized Gain (Loss) on Investments				150,000	0	0
Loss from unconsolidated joint ventures				59,840,000	2,570,000	85,110,000
Depreciation and amortization expense				749,775,000	717,336,000	683,751,000
Transaction costs				2,905,000	5,036,000	1,531,000
Operating expense				15,450,000	12,487,000	11,626,000
General and administrative expense				146,378,000	151,573,000	133,112,000
Gains (losses) from investments in securities				(6,453,000)	5,626,000	5,261,000
Other Income - assignment fee				6,624,000	0	0
Interest and other income (loss)				11,940,000	5,704,000	5,953,000
Sales-type and Direct Financing Leases, Profit (Loss)				(10,058,000)	0	0
Gains on sales of real estate				437,019,000	123,660,000	618,982,000
Other revenue				15,450,000	12,487,000	11,626,000
Company's share of Net Operating Income				1,883,796,000	1,735,740,000	1,626,131,000
Unconsolidated Joint Ventures [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense				(154,065,000)	(108,884,000)	(98,051,000)
Losses from early extinguishment of debt				1,327,000	0	0
Company's share of net operating income from joint ventures				(146,081,000)	(107,756,000)	(94,943,000)
Loss from unconsolidated joint ventures				59,840,000	2,570,000	85,110,000
Depreciation and amortization expense				(181,041,000)	(147,121,000)	(141,853,000)
Transaction costs				(837,000)	(470,000)	(1,027,000)
Gains on sales of real estate				0	0	(11,737,000)	[1]
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						94,943,000
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				957,265,000	561,993,000	979,979,000
Preferred Stock Redemption Charge				0	(6,412,000)	0
Preferred dividends / distributions				0	(2,560,000)	(10,500,000)
Noncontrolling interest in property partnerships				(74,857,000)	(70,806,000)	(48,260,000)
Interest expense				(437,139,000)	(423,346,000)	(431,717,000)
Losses from early extinguishment of debt				0	45,182,000	0
Unrealized Gain (Loss) on Investments				150,000	0	0
Loss from unconsolidated joint ventures				59,840,000	2,570,000	85,110,000
Depreciation and amortization expense				(742,293,000)	(709,035,000)
Transaction costs				(2,905,000)	(5,036,000)	(1,531,000)
General and administrative expense				(146,378,000)	(151,573,000)	(133,112,000)
Gains (losses) from investments in securities				6,453,000	(5,626,000)	(5,261,000)
Other Income - assignment fee				(6,624,000)	0	0
Interest and other income (loss)				(11,940,000)	(5,704,000)	(5,953,000)
Sales-type and Direct Financing Leases, Profit (Loss)				(10,058,000)	0	0
Gains on sales of real estate				(441,075,000)	(125,198,000)	(631,945,000)
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's common shareholders / unitholders				957,265,000	561,993,000	979,979,000
Preferred Stock Redemption Charge				0	6,412,000	0
Preferred dividends / distributions				0	2,560,000	10,500,000
Noncontrolling interest in property partnerships				74,857,000	70,806,000	48,260,000
Interest expense				437,139,000	423,346,000	431,717,000
Losses from early extinguishment of debt				0	45,182,000	0
Unrealized Gain (Loss) on Investments				150,000	0	0
Loss from unconsolidated joint ventures				59,840,000	2,570,000	85,110,000
Depreciation and amortization expense				742,293,000	709,035,000	676,666,000
Transaction costs				2,905,000	5,036,000	1,531,000
Operating expense				15,450,000	12,487,000	11,626,000
General and administrative expense				146,378,000	151,573,000	133,112,000
Gains (losses) from investments in securities				(6,453,000)	5,626,000	5,261,000
Other Income - assignment fee				6,624,000	0	0
Interest and other income (loss)				11,940,000	5,704,000	5,953,000
Sales-type and Direct Financing Leases, Profit (Loss)				(10,058,000)	0	0
Gains on sales of real estate				441,075,000	125,198,000	631,945,000
Other revenue				15,450,000	12,487,000	11,626,000
Company's share of Net Operating Income				1,883,796,000	1,735,740,000	1,626,131,000
Management Service [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue				(28,056,000)	(27,697,000)	(29,641,000)
Management Service [Member] | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue				28,056,000	27,697,000	29,641,000
Management Service [Member] | Boston Properties Limited Partnership
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue				(28,056,000)	(27,697,000)	(29,641,000)
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				28,056,000	27,697,000	29,641,000
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				191,812,000	186,304,000	162,887,000
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				191,812,000	186,304,000	162,887,000
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				$ 191,812,000	$ 186,304,000	$ 162,887,000
[1] For the year ended December 31, 2020, represents the gain on sale of Annapolis Junction Building Eight and two land parcels. The gain on sale of real estate is included in Loss from Unconsolidated Joint Ventures in the Company’s Consolidated Statements of Operations.

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