Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
ASSETS
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,358,363 and $7,172,718 at June 30, 2018 and December 31, 2017, respectively)	$ 21,526,520	$ 21,096,642
Less: accumulated depreciation (amounts related to VIEs of $(910,381) and $(854,172) at June 30, 2018 and December 31, 2017, respectively)	(4,745,590)	(4,589,634)
Total real estate	16,780,930	16,507,008
Cash and cash equivalents (amounts related to VIEs of $277,252 and $304,955 at June 30, 2018 and December 31, 2017, respectively)	472,555	434,767
Cash held in escrows (amounts related to VIEs of $6,099 and $6,135 at June 30, 2018 and December 31, 2017, respectively)	254,505	70,602
Investments in securities	30,063	29,161
Tenant and other receivables (amounts related to VIEs of $17,130 and $27,057 at June 30, 2018 and December 31, 2017, respectively)	63,660	92,186
Accrued rental income (amounts related to VIEs of $268,120 and $242,589 at June 30, 2018 and December 31, 2017, respectively)	912,652	861,575
Deferred charges, net (amounts related to VIEs of $264,973 and $281,678 at June 30, 2018 and December 31, 2017, respectively)	678,319	679,038
Prepaid expenses and other assets (amounts related to VIEs of $34,853 and $33,666 at June 30, 2018 and December 31, 2017, respectively)	85,972	77,971
Investments in unconsolidated joint ventures	682,507	619,925
Total assets	19,961,163	19,372,233
Liabilities:
Mortgage notes payable, net (amounts related to VIEs of $2,934,336 and $2,939,183 at June 30, 2018 and December 31, 2017, respectively)	2,972,052	2,979,281
Unsecured senior notes, net	7,251,578	7,247,330
Unsecured line of credit	0	45,000
Unsecured term loan, net	498,248	0
Accounts payable and accrued expenses (amounts related to VIEs of $80,098 and $106,683 at June 30, 2018 and December 31, 2017, respectively)	327,067	331,500
Dividends and distributions payable	139,263	139,040
Accrued interest payable (amounts related to VIEs of $6,669 and $6,907 at June 30, 2018 and December 31, 2017, respectively)	96,844	83,646
Other liabilities (amounts related to VIEs of $183,114 and $164,806 at June 30, 2018 and December 31, 2017, respectively)	462,869	443,980
Total liabilities	11,747,921	11,269,777
Commitments and contingencies	0	0
Equity / Capital:
Excess stock, $0.01 par value, 150,000,000 shares authorized, none issued or outstanding	0	0
Preferred stock, $.01 par value, 50,000,000 shares authorized
5.25% Series B cumulative redeemable preferred stock/unit, liquidation preference $2,500 per share/unit, 92,000 shares authorized, 80,000 shares/units issued and outstanding at June 30, 2018 and December 31, 2016	200,000	200,000
Common stock, $0.01 par value, 250,000,000 shares authorized, 154,490,429 and 154,404,186 issued and 154,411,529 and 154,325,286 outstanding at June 30, 2018 and December 31, 2017, respectively	1,544	1,543
Additional paid-in capital	6,391,460	6,377,908
Dividends in excess of earnings	(649,747)	(712,343)
Treasury common stock at cost, 78,900 shares at June 30, 2018 and December 31, 2017	(2,722)	(2,722)
Accumulated other comprehensive loss	(47,695)	(50,429)
Total stockholders’ equity attributable to Boston Properties, Inc.	5,892,840	5,813,957
Noncontrolling interests:
Common units of Boston Properties Limited Partnership	621,221	604,739
Property partnerships	1,699,181	1,683,760
Total equity / capital	8,213,242	8,102,456
Total liabilities and equity / capital	19,961,163	19,372,233
Boston Properties Limited Partnership
ASSETS
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,358,363 and $7,172,718 at June 30, 2018 and December 31, 2017, respectively)	21,118,909	20,685,164
Less: accumulated depreciation (amounts related to VIEs of $(910,381) and $(854,172) at June 30, 2018 and December 31, 2017, respectively)	(4,649,907)	(4,496,959)
Total real estate	16,469,002	16,188,205
Cash and cash equivalents (amounts related to VIEs of $277,252 and $304,955 at June 30, 2018 and December 31, 2017, respectively)	472,555	434,767
Cash held in escrows (amounts related to VIEs of $6,099 and $6,135 at June 30, 2018 and December 31, 2017, respectively)	254,505	70,602
Investments in securities	30,063	29,161
Tenant and other receivables (amounts related to VIEs of $17,130 and $27,057 at June 30, 2018 and December 31, 2017, respectively)	63,660	92,186
Accrued rental income (amounts related to VIEs of $268,120 and $242,589 at June 30, 2018 and December 31, 2017, respectively)	912,652	861,575
Deferred charges, net (amounts related to VIEs of $264,973 and $281,678 at June 30, 2018 and December 31, 2017, respectively)	678,319	679,038
Prepaid expenses and other assets (amounts related to VIEs of $34,853 and $33,666 at June 30, 2018 and December 31, 2017, respectively)	85,972	77,971
Investments in unconsolidated joint ventures	682,507	619,925
Total assets	19,649,235	19,053,430
Liabilities:
Mortgage notes payable, net (amounts related to VIEs of $2,934,336 and $2,939,183 at June 30, 2018 and December 31, 2017, respectively)	2,972,052	2,979,281
Unsecured senior notes, net	7,251,578	7,247,330
Unsecured line of credit	0	45,000
Unsecured term loan, net	498,248	0
Accounts payable and accrued expenses (amounts related to VIEs of $80,098 and $106,683 at June 30, 2018 and December 31, 2017, respectively)	327,067	331,500
Dividends and distributions payable	139,263	139,040
Accrued interest payable (amounts related to VIEs of $6,669 and $6,907 at June 30, 2018 and December 31, 2017, respectively)	96,844	83,646
Other liabilities (amounts related to VIEs of $183,114 and $164,806 at June 30, 2018 and December 31, 2017, respectively)	462,869	443,980
Total liabilities	11,747,921	11,269,777
Commitments and contingencies	0	0
Noncontrolling interest:
Redeemable partnership units—16,831,182 and 16,810,378 common units and 992,387 and 818,343 long term incentive units outstanding at redemption value at June 30, 2018 and December 31, 2017, respectively	2,235,432	2,292,263
Preferred stock, $.01 par value, 50,000,000 shares authorized
5.25% Series B cumulative redeemable preferred stock/unit, liquidation preference $2,500 per share/unit, 92,000 shares authorized, 80,000 shares/units issued and outstanding at June 30, 2018 and December 31, 2016	193,623	193,623
Noncontrolling interests:
Boston Properties Limited Partnership partners’ capital—1,722,351 and 1,719,540 general partner units and 152,689,178 and 152,605,746 limited partner units outstanding at June 30, 2018 and December 31, 2017, respectively	3,773,078	3,614,007
Noncontrolling interests in property partnerships	1,699,181	1,683,760
Total equity / capital	5,665,882	5,491,390
Total liabilities and equity / capital	$ 19,649,235	$ 19,053,430