Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net income (loss)	$ 291,424	$ 1,020,584	$ 631,932
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	830,813	749,775	717,336
Amortization of right of use assets - operating leases	1,940	2,427	3,516
Non-cash compensation expense	51,478	52,026	50,860
Loss (income) from unconsolidated joint ventures	239,543	59,840	2,570
Distributions of net cash flow from operations of unconsolidated joint ventures	24,637	26,827	21,542
Losses (gains) from investments in securities	(5,556)	6,453	(5,626)
Allowance for current expected credit losses (gains)	373	(224)	(1,207)
Non-cash portion of interest expense	30,523	25,831	23,368
Settlement of accreted debt discount on redemption of unsecured senior notes	0	0	(8,500)
Losses from early extinguishment of debt	0	0	45,182
Other Income - assignment fee	0	(6,624)	0
Gains on sales of real estate	(517)	(437,019)	(123,660)
Gain on sales-type lease	0	(10,058)	0
Unrealized Gain (Loss) on non-real estate Investments	(239)	150	0
Change in assets and liabilities:
Tenant and other receivables, net	(31,470)	(7,621)	4,820
Notes receivable, net	0	(152)	(545)
Accrued rental income, net	(99,539)	(98,075)	(101,548)
Prepaid expenses and other assets	(7,336)	20,099	(20,811)
Right of use assets - operating lease	(25,640)	0	0
Lease liabilities - operating leases	(121)	125	(23,599)
Accounts payable and accrued expenses	41,696	(22,777)	20,025
Accrued interest payable	29,910	8,989	(10,839)
Other liabilities	7,267	(24,120)	(28,739)
Tenant leasing costs	(77,666)	(84,057)	(62,850)
Total adjustments	1,010,096	261,815	501,295
Net cash provided by operating activities	1,301,520	1,282,399	1,133,227
Cash flows from investing activities:
Acquisitions of real estate	0	(1,320,273)	(222,260)
Construction in progress	(525,963)	(500,273)	(513,878)
Building and other capital improvements	(171,424)	(177,004)	(150,998)
Tenant improvements	(310,925)	(218,685)	(263,952)
Proceeds from sales of real estate	517	834,770	179,887
Acquisition of real estate (net of cash received upon consolidation)	(13,155)	0	0
Proceeds from assignment fee	0	6,624	0
Capital contributions to unconsolidated joint ventures	(192,650)	(277,581)	(98,152)
Capital distributions from unconsolidated joint ventures	32,787	37,122	122
Proceeds from Sale of Equity Method Investments	0	0	17,789
Investment in non-real estate investments	(2,187)	(2,404)	0
Issuance of note receivables (including related party)	(12,177)	0	0
Proceeds from note receivable	0	10,000	10,035
Investments in securities, net	1,496	4,902	1,451
Net cash used in investing activities	(1,193,681)	(1,602,802)	(1,039,956)
Cash flows from financing activities:
Proceeds from Secured Notes Payable	600,000	0	1,201,388
Repayments of mortgage notes payable	0	0	(832,296)
Proceeds from unsecured senior notes	747,727	749,557	1,695,996
Redemption of unsecured senior notes	(500,000)	0	(1,841,500)
Borrowings on unsecured line of credit	0	985,000	770,000
Repayments of unsecured line of credit	0	(1,130,000)	(625,000)
Borrowings on unsecured term loan	1,200,000	730,000	0
Redemption of preferred stock	0	0	(200,000)
Payments on finance lease obligations	0	0	1,250
Repayment of unsecured term loan	(730,000)	0	(500,000)
Deferred financing costs	(19,416)	(8,460)	(20,757)
Debt Issuance Costs	0	0	(16,186)
Debt prepayment and extinguishment costs	0	0	(43,036)
Net activity from equity transactions	367	(352)	24,214
Dividends and distributions	(687,809)	(685,019)	(683,753)
Proceeds from sale of interest in property partnerships and contributions from noncontrolling interests in property partnerships	244,541	849	18,002
Distributions to noncontrolling interests in property partnerships	(69,975)	(85,518)	(259,764)
Net cash provided by (used in) financing activities	767,916	556,057	(1,311,442)
Net increase (decrease) in cash and cash equivalents and cash held in escrows	875,755	235,654	(1,218,171)
Cash and cash equivalents and cash held in escrows, beginning of period	736,812	501,158	1,719,329
Cash and cash equivalents and cash held in escrows, end of period	1,612,567	736,812	501,158
Reconciliation of cash and cash equivalents and cash held in escrow
Cash and cash equivalents, beginning of period	690,333	452,692	1,668,742
Cash held in escrows, beginning of period	46,479	48,466	50,587
Cash and cash equivalents, end of period	1,531,477	690,333	452,692
Cash held in escrows,end of period	81,090	46,479	48,466
Supplemental disclosures:
Cash paid for interest	553,989	449,903	465,442
Interest capitalized	42,633	52,130	53,097
Non-cash investing and financing activities:
Write-off of fully depreciated real estate	(135,093)	(119,534)	(239,317)
Change in real estate included in accounts payable and accrued expenses	3,668	97,586	(25,183)
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	141,179	0	26,887
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	163,056	0	0
Non-cash contributions from noncontrolling interest in property partnerhips	17,519	0	0
Capitalized operating lease costs	12,580	0	0
Construction in progress from prepaid expenses and other assets	25,577	0	0
Investment in unconsolidated joint ventures eliminated upon consolidation	183,817	0	0
Mortgage notes payable recorded upon consolidation	300,000	0	0
Real estate and intangibles recorded upon consolidation	(490,720)	0	0
Interest rate swaps recorded upon consolidation	(7,337)	0	0
Construction in progress, net deconsolidated	0	(11,316)	(299,947)
Investment in unconsolidated joint ventures recorded upon deconsolidation	0	11,316	107,132
Sales-type lease origination	0	13,045	0
Derecognition of assets in exchange for sales-type lease obligation	0	(2,987)	0
Prepaid expenses and other assets, net deconsolidated	0	0	(5,011)
Assumption of mortgage notes payable	0	0	200,311
Mortgage notes payable, net deconsolidation	0	0	(198,381)
Issuance of operating partnership units	0	0	99,689
Dividends and distributions declared but not paid	171,176	170,643	169,859
Conversions of noncontrolling interests to stockholders’ equity	3,794	6,539	18,386
Issuance of restricted securities to employees and non-employee directors	48,141	48,417	44,405
Cash
Cash flows from financing activities:
Proceeds from sale of interest in property partnerships and contributions from noncontrolling interests in property partnerships	227,022	849	18,002
Boston Properties Limited Partnership
Net income (loss)	298,432	1,032,122	641,771
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	823,805	742,293	709,035
Amortization of right of use assets - operating leases	1,940	2,427	3,516
Non-cash compensation expense	51,478	52,026	50,860
Loss (income) from unconsolidated joint ventures	239,543	59,840	2,570
Distributions of net cash flow from operations of unconsolidated joint ventures	24,637	26,827	21,542
Losses (gains) from investments in securities	(5,556)	6,453	(5,626)
Allowance for current expected credit losses (gains)	373	(224)	(1,207)
Non-cash portion of interest expense	30,523	25,831	23,368
Settlement of accreted debt discount on redemption of unsecured senior notes	0	0	(8,500)
Losses from early extinguishment of debt	0	0	45,182
Other Income - assignment fee	0	(6,624)	0
Gains on sales of real estate	(517)	(441,075)	(125,198)
Gain on sales-type lease	0	(10,058)	0
Unrealized Gain (Loss) on non-real estate Investments	(239)	150	0
Change in assets and liabilities:
Tenant and other receivables, net	(31,470)	(7,621)	4,820
Notes receivable, net	0	(152)	(545)
Accrued rental income, net	(99,539)	(98,075)	(101,548)
Prepaid expenses and other assets	(7,336)	20,099	(20,811)
Right of use assets - operating lease	(25,640)	0	0
Lease liabilities - operating leases	(121)	125	(23,599)
Accounts payable and accrued expenses	41,696	(22,777)	20,025
Accrued interest payable	29,910	8,989	(10,839)
Other liabilities	7,267	(24,120)	(28,739)
Tenant leasing costs	(77,666)	(84,057)	(62,850)
Total adjustments	1,003,088	250,277	491,456
Net cash provided by operating activities	1,301,520	1,282,399	1,133,227
Cash flows from investing activities:
Acquisitions of real estate	0	(1,320,273)	(222,260)
Construction in progress	(525,963)	(500,273)	(513,878)
Building and other capital improvements	(171,424)	(177,004)	(150,998)
Tenant improvements	(310,925)	(218,685)	(263,952)
Proceeds from sales of real estate	517	834,770	179,887
Acquisition of real estate (net of cash received upon consolidation)	(13,155)	0	0
Proceeds from assignment fee	0	6,624	0
Capital contributions to unconsolidated joint ventures	(192,650)	(277,581)	(98,152)
Capital distributions from unconsolidated joint ventures	32,787	37,122	122
Proceeds from Sale of Equity Method Investments	0	0	17,789
Investment in non-real estate investments	(2,187)	(2,404)	0
Issuance of note receivables (including related party)	(12,177)	0	0
Proceeds from note receivable	0	10,000	10,035
Investments in securities, net	1,496	4,902	1,451
Net cash used in investing activities	(1,193,681)	(1,602,802)	(1,039,956)
Cash flows from financing activities:
Proceeds from Secured Notes Payable	600,000	0	1,201,388
Repayments of mortgage notes payable	0	0	(832,296)
Proceeds from unsecured senior notes	747,727	749,557	1,695,996
Redemption of unsecured senior notes	(500,000)	0	(1,841,500)
Borrowings on unsecured line of credit	0	985,000	770,000
Repayments of unsecured line of credit	0	(1,130,000)	(625,000)
Borrowings on unsecured term loan	1,200,000	730,000	0
Redemption of preferred stock	0	0	(200,000)
Payments on finance lease obligations	0	0	1,250
Repayment of unsecured term loan	(730,000)	0	(500,000)
Deferred financing costs	(19,416)	(8,460)	(20,757)
Debt Issuance Costs	0	0	(16,186)
Debt prepayment and extinguishment costs	0	0	(43,036)
Net activity from equity transactions	367	(352)	24,214
Dividends and distributions	(687,809)	(685,019)	(683,753)
Distributions to noncontrolling interests in property partnerships	(69,975)	(85,518)	(259,764)
Net cash provided by (used in) financing activities	767,916	556,057	(1,311,442)
Net increase (decrease) in cash and cash equivalents and cash held in escrows	875,755	235,654	(1,218,171)
Cash and cash equivalents and cash held in escrows, beginning of period	736,812	501,158	1,719,329
Cash and cash equivalents and cash held in escrows, end of period	1,612,567	736,812	501,158
Reconciliation of cash and cash equivalents and cash held in escrow
Cash and cash equivalents, beginning of period	690,333	452,692	1,668,742
Cash held in escrows, beginning of period	46,479	48,466	50,587
Cash and cash equivalents, end of period	1,531,477	690,333	452,692
Cash held in escrows,end of period	81,090	46,479	48,466
Supplemental disclosures:
Cash paid for interest	553,989	449,903	465,442
Interest capitalized	42,633	52,130	53,097
Non-cash investing and financing activities:
Write-off of fully depreciated real estate	(133,844)	(119,534)	(238,003)
Change in real estate included in accounts payable and accrued expenses	3,668	97,586	(25,183)
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	141,179	0	26,887
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	163,056	0	0
Non-cash contributions from noncontrolling interest in property partnerhips	17,519	0	0
Capitalized operating lease costs	12,580	0	0
Construction in progress from prepaid expenses and other assets	25,577	0	0
Investment in unconsolidated joint ventures eliminated upon consolidation	183,817	0	0
Mortgage notes payable recorded upon consolidation	300,000	0	0
Real estate and intangibles recorded upon consolidation	(490,720)	0	0
Interest rate swaps recorded upon consolidation	(7,337)	0	0
Construction in progress, net deconsolidated	0	(11,316)	(299,947)
Investment in unconsolidated joint ventures recorded upon deconsolidation	0	11,316	107,132
Sales-type lease origination	0	13,045	0
Derecognition of assets in exchange for sales-type lease obligation	0	(2,987)	0
Prepaid expenses and other assets, net deconsolidated	0	0	(5,011)
Assumption of mortgage notes payable	0	0	200,311
Mortgage notes payable, net deconsolidation	0	0	(198,381)
Issuance of operating partnership units	0	0	99,689
Dividends and distributions declared but not paid	171,176	170,643	169,859
Conversions of noncontrolling interests to stockholders’ equity	3,794	6,539	18,386
Issuance of restricted securities to employees and non-employee directors	48,141	48,417	44,405
Boston Properties Limited Partnership | Cash
Cash flows from financing activities:
Proceeds from sale of interest in property partnerships and contributions from noncontrolling interests in property partnerships	$ 227,022	$ 849	$ 18,002