Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021		Dec. 31, 2020
ASSETS
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,664,480 and $6,592,019 at June 30, 2021 and December 31, 2020, respectively)	$ 23,417,175		$ 22,969,110
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at June 30, 2021 and December 31, 2020, respectively)	237,765		237,393
Right of use assets - operating leases	170,331	[1]	146,406
Less: accumulated depreciation (amounts related to VIEs of $(1,235,346) and $(1,158,548) at June 30, 2021 and December 31, 2020, respectively)	(5,752,818)		(5,534,102)
Real estate and development in process, net	18,072,453		17,818,807
Cash and cash equivalents (amounts related to VIEs of $335,837 and $340,642 at June 30, 2021 and December 31, 2020, respectively)	557,307		1,668,742
Cash held in escrows	79,973		50,587
Investments in securities	41,476		39,457
Tenant and other receivables, net (amounts related to VIEs of $5,298 and $10,911 at June 30, 2021 and December 31, 2020, respectively)	58,624		77,411
Related party note receivable, net	77,872		77,552
Notes receivable, net	19,087		18,729
Accrued rental income, net (amounts related to VIEs of $346,443 and $336,594 at June 30, 2021 and December 31, 2020, respectively)	1,172,411		1,122,502
Deferred charges, net (amounts related to VIEs of $173,578 and $183,306 at June 30, 2021 and December 31, 2020, respectively)	627,338		640,085
Prepaid expenses and other assets (amounts related to VIEs of $12,441 and $13,137 at June 30, 2021 and December 31, 2020, respectively)	46,946		33,840
Investments in unconsolidated joint ventures	1,305,589		1,310,478
Total assets	22,059,076		22,858,190
Liabilities:
Mortgage notes payable, net (amounts related to VIEs of $2,901,709 and $2,907,590 at June 30, 2021 and December 31, 2020, respectively)	2,901,709		2,909,081
Unsecured senior notes, net	9,634,356		9,639,287
Unsecured line of credit	0		0
Unsecured term loan, net	0		499,390
Lease liabilities - finance leases (amounts related to VIEs of $20,382 and $20,306 at June 30, 2021 and December 31, 2020, respectively)	243,381		236,492
Lease liabilities - operating leases	226,594		201,713
Accounts payable and accrued expenses (amounts related to VIEs of $40,100 and $23,128 at June 30, 2021 and December 31, 2020, respectively)	305,969		336,264
Dividends and distributions payable	169,718		171,082
Accrued interest payable	107,386		106,288
Other liabilities (amounts related to VIEs of $129,477 and $158,805 at June 30, 2021 and December 31, 2020, respectively)	370,990		412,084
Total liabilities	13,960,103		14,511,681
Redeemable deferred stock units— 78,362 and 72,966 units outstanding at redemption value at June 30, 2021 and December 31, 2020, respectively	8,980		6,897
Equity / Capital:
Excess stock, $0.01 par value, 150,000,000 shares authorized, none issued or outstanding	0		0
Preferred stock, $0.01 par value, 50,000,000 shares authorized;
5.25% Series B cumulative redeemable preferred stock / units, liquidation preference $2,500 per share / unit, 80,000 shares / units issued and outstanding at December 31, 2020	0		200,000
Common stock, $0.01 par value, 250,000,000 shares authorized, 156,214,859 and 155,797,725 issued and 156,135,959 and 155,718,825 outstanding at June 30, 2021 and December 31, 2020, respectively	1,561		1,557
Additional paid-in capital	6,405,916		6,356,791
Dividends in excess of earnings	(612,247)		(509,653)
Treasury common stock at cost, 78,900 shares at June 30, 2021 and December 31, 2020	(2,722)		(2,722)
Accumulated other comprehensive loss	(43,166)		(49,890)
Total stockholders' equity attributable to Boston Properties, Inc.	5,749,342		5,996,083
Noncontrolling interests:
Common units of the Operating Partnership	615,308		616,596
Property partnerships	1,725,343		1,726,933
Total equity / capital	8,089,993		8,339,612
Total liabilities and equity / capital	22,059,076		22,858,190
Boston Properties Limited Partnership
ASSETS
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,664,480 and $6,592,019 at June 30, 2021 and December 31, 2020, respectively)	23,041,680		22,592,301
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at June 30, 2021 and December 31, 2020, respectively)	237,765		237,393
Right of use assets - operating leases	170,331	[1]	146,406
Less: accumulated depreciation (amounts related to VIEs of $(1,235,346) and $(1,158,548) at June 30, 2021 and December 31, 2020, respectively)	(5,643,781)		(5,428,576)
Real estate and development in process, net	17,805,995		17,547,524
Cash and cash equivalents (amounts related to VIEs of $335,837 and $340,642 at June 30, 2021 and December 31, 2020, respectively)	557,307		1,668,742
Cash held in escrows	79,973		50,587
Investments in securities	41,476		39,457
Tenant and other receivables, net (amounts related to VIEs of $5,298 and $10,911 at June 30, 2021 and December 31, 2020, respectively)	58,624		77,411
Related party note receivable, net	77,872		77,552
Notes receivable, net	19,087		18,729
Accrued rental income, net (amounts related to VIEs of $346,443 and $336,594 at June 30, 2021 and December 31, 2020, respectively)	1,172,411		1,122,502
Deferred charges, net (amounts related to VIEs of $173,578 and $183,306 at June 30, 2021 and December 31, 2020, respectively)	627,338		640,085
Prepaid expenses and other assets (amounts related to VIEs of $12,441 and $13,137 at June 30, 2021 and December 31, 2020, respectively)	46,946		33,840
Investments in unconsolidated joint ventures	1,305,589		1,310,478
Total assets	21,792,618		22,586,907
Liabilities:
Mortgage notes payable, net (amounts related to VIEs of $2,901,709 and $2,907,590 at June 30, 2021 and December 31, 2020, respectively)	2,901,709		2,909,081
Unsecured senior notes, net	9,634,356		9,639,287
Unsecured line of credit	0		0
Unsecured term loan, net	0		499,390
Lease liabilities - finance leases (amounts related to VIEs of $20,382 and $20,306 at June 30, 2021 and December 31, 2020, respectively)	243,381		236,492
Lease liabilities - operating leases	226,594		201,713
Accounts payable and accrued expenses (amounts related to VIEs of $40,100 and $23,128 at June 30, 2021 and December 31, 2020, respectively)	305,969		336,264
Dividends and distributions payable	169,718		171,082
Accrued interest payable	107,386		106,288
Other liabilities (amounts related to VIEs of $129,477 and $158,805 at June 30, 2021 and December 31, 2020, respectively)	370,990		412,084
Total liabilities	13,960,103		14,511,681
Redeemable deferred stock units— 78,362 and 72,966 units outstanding at redemption value at June 30, 2021 and December 31, 2020, respectively	8,980		6,897
Redeemable partnership units— 16,038,056 and 16,037,121 common units and 1,489,456 and 1,336,115 long term incentive units outstanding at redemption value at June 30, 2021 and December 31, 2020, respectively	2,008,478		1,643,024
Preferred stock, $0.01 par value, 50,000,000 shares authorized;
5.25% Series B cumulative redeemable preferred stock / units, liquidation preference $2,500 per share / unit, 80,000 shares / units issued and outstanding at December 31, 2020	0		193,623
Boston Properties Limited Partnership partners’ capital— 1,736,635 and 1,730,921 general partner units and 154,399,324 and 153,987,904 limited partner units outstanding at June 30, 2021 and December 31, 2020, respectively	4,132,880		4,554,639
Accumulated other comprehensive loss	(43,166)		(49,890)
Total partners’ capital	4,089,714		4,698,372
Noncontrolling interests in property partnerships	1,725,343		1,726,933
Noncontrolling interests:
Total equity / capital	5,815,057		6,425,305
Total liabilities and equity / capital	$ 21,792,618		$ 22,586,907

[1] See Note 4.