Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net income attributable to the company's common shareholders / unitholders	$ 222,989,000	$ 111,703,000	$ 366,044,000	$ 203,372,000
Preferred Stock Redemption Charge	0	0	0	(6,412,000)
Preferred dividends / distributions	0	0	0	(2,560,000)
Noncontrolling interest-common units of the Operating Partnership	(25,708,000)	(12,383,000)	(42,061,000)	(23,422,000)
Noncontrolling interest in property partnerships	(18,546,000)	(17,164,000)	(36,095,000)	(33,631,000)
Interest expense	(104,142,000)	(106,319,000)	(205,370,000)	(214,221,000)
Loss from early extinguishment of debt	0	0	0	898,000
Company's share of net operating income from joint ventures	(484,042,000)	(453,169,000)	(953,358,000)	(897,116,000)
Depreciation and amortization expense	(183,146,000)	(183,838,000)	(360,770,000)	(360,403,000)
Transaction costs	(496,000)	(751,000)	(496,000)	(1,082,000)
General and administrative expense	(34,665,000)	(38,405,000)	(77,859,000)	(83,364,000)
Gains (losses) from investments in securities	4,716,000	(2,275,000)	6,978,000	(3,934,000)
Other Income - assignment fee	(6,624,000)	0	(6,624,000)	0
Interest and other income (loss)	(1,195,000)	(1,452,000)	(2,423,000)	(2,620,000)
Gains on sales of real estate	(96,247,000)	(7,756,000)	(118,948,000)	(7,756,000)
Income (loss) from unconsolidated joint ventures	54,000	1,373,000	(2,135,000)	(3,852,000)
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	222,989,000	111,703,000	366,044,000	203,372,000
Preferred Stock Redemption Charge	0	0	0	6,412,000
Preferred dividends / distributions	0	0	0	2,560,000
Noncontrolling interest-common units of the Operating Partnership	25,708,000	12,383,000	42,061,000	23,422,000
Noncontrolling interest in property partnerships	18,546,000	17,164,000	36,095,000	33,631,000
Interest expense	104,142,000	106,319,000	205,370,000	214,221,000
Loss from early extinguishment of debt	0	0	0	898,000
Depreciation and amortization expense	183,146,000	183,838,000	360,770,000	360,403,000
Transaction costs	496,000	751,000	496,000	1,082,000
Operating expense	3,239,000	2,655,000	7,304,000	6,160,000
General and administrative expense	34,665,000	38,405,000	77,859,000	83,364,000
Gains (losses) from investments in securities	(4,716,000)	2,275,000	(6,978,000)	3,934,000
Other Income - assignment fee	6,624,000	0	6,624,000	0
Interest and other income (loss)	1,195,000	1,452,000	2,423,000	2,620,000
Gains on sales of real estate	96,247,000	7,756,000	118,948,000	7,756,000
Income (loss) from unconsolidated joint ventures	(54,000)	(1,373,000)	2,135,000	3,852,000
Other revenue	3,239,000	2,655,000	7,304,000	6,160,000
Company's share of Net Operating Income	471,890,000	432,299,000	931,472,000	856,665,000
Unconsolidated Joint Ventures [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense	(32,219,000)	(25,636,000)	(62,592,000)	(51,192,000)
Loss from early extinguishment of debt	0	0	1,327,000	0
Depreciation and amortization expense	(43,293,000)	(33,627,000)	(87,957,000)	(67,730,000)
Transaction costs	(811,000)	0	(811,000)	(7,000)
Income (loss) from unconsolidated joint ventures	54,000	1,373,000	(2,135,000)	(3,852,000)
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	35,710,000	25,417,000	73,031,000	50,212,000
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	253,788,000	125,846,000	415,617,000	231,619,000
Preferred Stock Redemption Charge	0	0	0	(6,412,000)
Preferred dividends / distributions	0	0	0	(2,560,000)
Noncontrolling interest in property partnerships	(18,546,000)	(17,164,000)	(36,095,000)	(33,631,000)
Interest expense	(104,142,000)	(106,319,000)	(205,370,000)	(214,221,000)
Loss from early extinguishment of debt	0	0	0	898,000
Depreciation and amortization expense	(181,416,000)	(182,078,000)	(357,302,000)	(355,578,000)
Transaction costs	(496,000)	(751,000)	(496,000)	(1,082,000)
General and administrative expense	(34,665,000)	(38,405,000)	(77,859,000)	(83,364,000)
Gains (losses) from investments in securities	4,716,000	(2,275,000)	6,978,000	(3,934,000)
Other Income - assignment fee	(6,624,000)	0	(6,624,000)	0
Interest and other income (loss)	(1,195,000)	(1,452,000)	(2,423,000)	(2,620,000)
Gains on sales of real estate	(99,608,000)	(7,756,000)	(122,992,000)	(7,756,000)
Income (loss) from unconsolidated joint ventures	54,000	1,373,000	(2,135,000)	(3,852,000)
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	253,788,000	125,846,000	415,617,000	231,619,000
Preferred Stock Redemption Charge	0	0		6,412,000
Preferred dividends / distributions	0	0	0	2,560,000
Noncontrolling interest in property partnerships	18,546,000	17,164,000	36,095,000	33,631,000
Interest expense	104,142,000	106,319,000	205,370,000	214,221,000
Loss from early extinguishment of debt	0	0	0	898,000
Depreciation and amortization expense	181,416,000	182,078,000	357,302,000	355,578,000
Transaction costs	496,000	751,000	496,000	1,082,000
Operating expense	3,239,000	2,655,000	7,304,000	6,160,000
General and administrative expense	34,665,000	38,405,000	77,859,000	83,364,000
Gains (losses) from investments in securities	(4,716,000)	2,275,000	(6,978,000)	3,934,000
Other Income - assignment fee	6,624,000	0	6,624,000	0
Interest and other income (loss)	1,195,000	1,452,000	2,423,000	2,620,000
Gains on sales of real estate	99,608,000	7,756,000	122,992,000	7,756,000
Income (loss) from unconsolidated joint ventures	(54,000)	(1,373,000)	2,135,000	3,852,000
Other revenue	3,239,000	2,655,000	7,304,000	6,160,000
Company's share of Net Operating Income	471,890,000	432,299,000	931,472,000	856,665,000
Management Service [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	(6,354,000)	(7,284,000)	(12,185,000)	(14,087,000)
Management Service [Member] | Segment Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	6,354,000	7,284,000	12,185,000	14,087,000
Management Service [Member] | Boston Properties Limited Partnership
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other revenue	(6,354,000)	(7,284,000)	(12,185,000)	(14,087,000)
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	6,354,000	7,284,000	12,185,000	14,087,000
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	47,862,000	46,287,000	94,917,000	90,663,000
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	47,862,000	46,287,000	94,917,000	90,663,000
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	$ 47,862,000	$ 46,287,000	$ 94,917,000	$ 90,663,000