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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $8,005,124 and $7,797,430 at December 31, 2025 and December 31, 2024, respectively)	$ 28,241,879	$ 27,870,623
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2025 and December 31, 2024, respectively)	372,470	372,922
Right of use assets - operating leases (amounts related to VIEs of $0 and $140,558 at December 31, 2025 and December 31, 2024, respectively)	325,841	334,767
Less: accumulated depreciation (amounts related to VIEs of $(1,763,988) and $(1,628,274) at December 31, 2025 and December 31, 2024, respectively)	(8,040,311)	(7,528,057)
Cash and cash equivalents (amounts related to VIEs of $255,631 and $373,737 at December 31, 2025 and December 31, 2024, respectively)	1,478,206	1,254,882
Cash held in escrows (amounts related to VIEs of $10,319 and $4,979 at December 31, 2025 and December 31, 2024, respectively)	79,060	80,314
Tenant and other receivables, net (amounts related to VIEs of $30,989 and $20,435 at December 31, 2025 and December 31, 2024, respectively)	92,625	107,453
Accrued rental income, net (amounts related to VIEs of $470,734 and $435,110 at December 31, 2025 and December 31, 2024, respectively)	1,538,515	1,466,220
Deferred charges, net (amounts related to VIEs of $204,924 and $211,726 at December 31, 2025 and December 31, 2024, respectively)	847,690	813,345
Prepaid expenses and other assets (amounts related to VIEs of $14,509 and $15,036 at December 31, 2025 and December 31, 2024, respectively)	108,105	70,839
Assets held for sale	24,770	0
Mortgage notes payable, net (amounts related to VIEs of $3,286,870 and $3,282,027 at December 31, 2025 and December 31, 2024, respectively)	4,280,067	4,276,609
Lease liabilities - finance leases (amounts related to VIEs of $21,074 and $20,931 at December 31, 2025 and December 31, 2024, respectively)	360,039	370,885
Lease liabilities - operating leases (amounts related to VIEs of $0 and $157,691 at December 31, 2025 and December 31, 2024, respectively)	389,213	392,686
Accounts payable and accrued expenses (amounts related to VIEs of $88,849 and $115,808 at December 31, 2025 and December 31, 2024, respectively)	480,017	401,874
Other liabilities (amounts related to VIEs of $95,209 and $126,202 at December 31, 2025 and December 31, 2024, respectively)	$ 386,074	$ 450,796
Reedemable deferred stock units, units	111,701	128,227
Limited Partners' Capital Account, Units Outstanding (in units)	156,780,294
General Partners' Capital Account, Units Outstanding (in units)	1,768,004
Excess stock, par value	$ 0.01	$ 0.01
Excess stock, shares authorized	150,000,000	150,000,000
Excess stock, shares outstanding	0	0
Excess stock, shares issued	0	0
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock / units, shares / units issued (in shares / units)	0	0
Preferred stock / units, shares / units outstanding (in shares / units)	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	158,627,198	158,253,895
Common Stock, Shares, Outstanding	158,548,298	158,174,995
Treasury common stock at cost, shares	78,900	78,900
Related Party
Related party note receivable, net	$ 28,346	$ 88,779
Accounts payable and accrued expenses (amounts related to VIEs of $88,849 and $115,808 at December 31, 2025 and December 31, 2024, respectively)	800	700
Nonrelated Party
Related party note receivable, net	9,373	4,947
Boston Properties Limited Partnership
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $8,005,124 and $7,797,430 at December 31, 2025 and December 31, 2024, respectively)	27,884,397	27,504,358
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2025 and December 31, 2024, respectively)	372,470	372,922
Right of use assets - operating leases (amounts related to VIEs of $0 and $140,558 at December 31, 2025 and December 31, 2024, respectively)	325,841	334,767
Less: accumulated depreciation (amounts related to VIEs of $(1,763,988) and $(1,628,274) at December 31, 2025 and December 31, 2024, respectively)	(7,906,629)	(7,397,882)
Cash and cash equivalents (amounts related to VIEs of $255,631 and $373,737 at December 31, 2025 and December 31, 2024, respectively)	1,478,206	1,254,882
Cash held in escrows (amounts related to VIEs of $10,319 and $4,979 at December 31, 2025 and December 31, 2024, respectively)	79,060	80,314
Tenant and other receivables, net (amounts related to VIEs of $30,989 and $20,435 at December 31, 2025 and December 31, 2024, respectively)	92,625	107,453
Accrued rental income, net (amounts related to VIEs of $470,734 and $435,110 at December 31, 2025 and December 31, 2024, respectively)	1,538,515	1,466,220
Deferred charges, net (amounts related to VIEs of $204,924 and $211,726 at December 31, 2025 and December 31, 2024, respectively)	847,690	813,345
Prepaid expenses and other assets (amounts related to VIEs of $14,509 and $15,036 at December 31, 2025 and December 31, 2024, respectively)	108,105	70,839
Assets held for sale	24,770	0
Mortgage notes payable, net (amounts related to VIEs of $3,286,870 and $3,282,027 at December 31, 2025 and December 31, 2024, respectively)	4,280,067	4,276,609
Lease liabilities - finance leases (amounts related to VIEs of $21,074 and $20,931 at December 31, 2025 and December 31, 2024, respectively)	360,039	370,885
Lease liabilities - operating leases (amounts related to VIEs of $0 and $157,691 at December 31, 2025 and December 31, 2024, respectively)	389,213	392,686
Accounts payable and accrued expenses (amounts related to VIEs of $88,849 and $115,808 at December 31, 2025 and December 31, 2024, respectively)	480,017	401,874
Other liabilities (amounts related to VIEs of $95,209 and $126,202 at December 31, 2025 and December 31, 2024, respectively)	$ 386,074	$ 450,796
Reedemable deferred stock units, units	111,701	128,227
Limited Partners' Capital Account, Units Outstanding (in units)	156,780,294	156,412,584
General Partners' Capital Account, Units Outstanding (in units)	1,768,004	1,762,411
NonControlling Interest Redeemable Partnership Units Common Units Shares Outstanding	15,590,009	15,730,882
NonControlling Interest Redeemable Partnership Units Common Units Long Term Incentive Units At Redemption Value Shares Outstanding	2,662,140	2,335,229
Boston Properties Limited Partnership | Related Party
Related party note receivable, net	$ 28,346	$ 88,779
Boston Properties Limited Partnership | Nonrelated Party
Related party note receivable, net	9,373	4,947
Variable Interest Entity, Primary Beneficiary [Member]
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $8,005,124 and $7,797,430 at December 31, 2025 and December 31, 2024, respectively)	8,005,124	7,797,430
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2025 and December 31, 2024, respectively)	21,000	21,000
Right of use assets - operating leases (amounts related to VIEs of $0 and $140,558 at December 31, 2025 and December 31, 2024, respectively)	0	140,558
Less: accumulated depreciation (amounts related to VIEs of $(1,763,988) and $(1,628,274) at December 31, 2025 and December 31, 2024, respectively)	(1,763,988)	(1,628,274)
Cash and cash equivalents (amounts related to VIEs of $255,631 and $373,737 at December 31, 2025 and December 31, 2024, respectively)	255,631	373,737
Cash held in escrows (amounts related to VIEs of $10,319 and $4,979 at December 31, 2025 and December 31, 2024, respectively)	10,319	4,979
Tenant and other receivables, net (amounts related to VIEs of $30,989 and $20,435 at December 31, 2025 and December 31, 2024, respectively)	30,989	20,435
Accrued rental income, net (amounts related to VIEs of $470,734 and $435,110 at December 31, 2025 and December 31, 2024, respectively)	470,734	435,110
Deferred charges, net (amounts related to VIEs of $204,924 and $211,726 at December 31, 2025 and December 31, 2024, respectively)	204,924	211,726
Prepaid expenses and other assets (amounts related to VIEs of $14,509 and $15,036 at December 31, 2025 and December 31, 2024, respectively)	14,509	15,036
Mortgage notes payable, net (amounts related to VIEs of $3,286,870 and $3,282,027 at December 31, 2025 and December 31, 2024, respectively)	3,286,870	3,282,027
Lease liabilities - finance leases (amounts related to VIEs of $21,074 and $20,931 at December 31, 2025 and December 31, 2024, respectively)	21,074	20,931
Lease liabilities - operating leases (amounts related to VIEs of $0 and $157,691 at December 31, 2025 and December 31, 2024, respectively)	0	157,691
Accounts payable and accrued expenses (amounts related to VIEs of $88,849 and $115,808 at December 31, 2025 and December 31, 2024, respectively)	88,849	115,808
Other liabilities (amounts related to VIEs of $95,209 and $126,202 at December 31, 2025 and December 31, 2024, respectively)	95,209	126,202
Variable Interest Entity, Primary Beneficiary [Member] | Boston Properties Limited Partnership
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $8,005,124 and $7,797,430 at December 31, 2025 and December 31, 2024, respectively)	8,005,124	7,797,430
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2025 and December 31, 2024, respectively)	21,000	21,000
Right of use assets - operating leases (amounts related to VIEs of $0 and $140,558 at December 31, 2025 and December 31, 2024, respectively)	0	140,558
Less: accumulated depreciation (amounts related to VIEs of $(1,763,988) and $(1,628,274) at December 31, 2025 and December 31, 2024, respectively)	(1,763,988)	(1,628,274)
Cash and cash equivalents (amounts related to VIEs of $255,631 and $373,737 at December 31, 2025 and December 31, 2024, respectively)	255,631	373,737
Cash held in escrows (amounts related to VIEs of $10,319 and $4,979 at December 31, 2025 and December 31, 2024, respectively)	10,319	4,979
Tenant and other receivables, net (amounts related to VIEs of $30,989 and $20,435 at December 31, 2025 and December 31, 2024, respectively)	30,989	20,435
Accrued rental income, net (amounts related to VIEs of $470,734 and $435,110 at December 31, 2025 and December 31, 2024, respectively)	470,734	435,110
Deferred charges, net (amounts related to VIEs of $204,924 and $211,726 at December 31, 2025 and December 31, 2024, respectively)	204,924	211,726
Prepaid expenses and other assets (amounts related to VIEs of $14,509 and $15,036 at December 31, 2025 and December 31, 2024, respectively)	14,509	15,036
Mortgage notes payable, net (amounts related to VIEs of $3,286,870 and $3,282,027 at December 31, 2025 and December 31, 2024, respectively)	3,286,870	3,282,027
Lease liabilities - finance leases (amounts related to VIEs of $21,074 and $20,931 at December 31, 2025 and December 31, 2024, respectively)	21,074	20,931
Lease liabilities - operating leases (amounts related to VIEs of $0 and $157,691 at December 31, 2025 and December 31, 2024, respectively)	0	157,691
Accounts payable and accrued expenses (amounts related to VIEs of $88,849 and $115,808 at December 31, 2025 and December 31, 2024, respectively)	88,849	115,808
Other liabilities (amounts related to VIEs of $95,209 and $126,202 at December 31, 2025 and December 31, 2024, respectively)	$ 95,209	$ 126,202

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