Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Real estate, at cost	$ 19,481,535	$ 19,236,403
Less: accumulated depreciation	(3,925,894)	(3,547,659)
Total real estate	15,555,641	15,688,744
Cash and cash equivalents	723,718	1,763,079
Cash held in escrows	73,790	487,321
Investments in securities	20,380	19,459
Tenant and other receivables (net of allowance for doubtful accounts of $1,197 and $1,142, respectively)	97,865	46,595
Accrued rental income (net of allowance of $2,775 and $1,499, respectively)	754,883	691,999
Deferred charges, net	732,837	831,744
Prepaid expenses and other assets	185,118	164,432
Investments in unconsolidated joint ventures	235,224	193,394
Total assets	18,379,456	19,886,767
Liabilities:
Mortgage notes payable	3,438,714	4,309,484
Unsecured senior notes (net of discount of $10,683 and $12,296, respectively)	5,289,317	5,287,704
Unsecured line of credit	0	0
Mezzanine notes payable	308,482	309,796
Outside members’ notes payable	180,000	180,000
Accounts payable and accrued expenses	274,709	243,263
Dividends and distributions payable	327,320	882,472
Accrued interest payable	190,386	163,532
Other liabilities	483,601	502,255
Total liabilities	10,492,529	11,878,506
Commitments and contingencies	0	0
Noncontrolling interest:
Redeemable preferred units	0	633
Redeemable interest in property partnership	0	104,692
Equity:
Excess stock, $.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 / units, liquidation preference $2,500 per share / unit, 80,000 shares / units issued and outstanding at December 31, 2015 and December 31, 2014, respectively	200,000	200,000
Common stock, $.01 par value, 250,000,000 shares authorized, 153,658,866 and 153,192,845 issued and 153,579,966 and 153,113,945 outstanding at December 31, 2015 and December 31, 2014, respectively	1,536	1,531
Additional paid-in capital	6,305,687	6,270,257
Dividends in excess of earnings	(780,952)	(762,464)
Treasury common stock at cost, 78,900 shares at December 31, 2015 and December 31, 2014	(2,722)	(2,722)
Accumulated other comprehensive loss	(14,114)	(9,304)
Total stockholders' equity attributable to Boston Properties, Inc.	5,709,435	5,697,298
Noncontrolling interests:
Common units of the Operating Partnership	603,092	603,171
Property partnerships	1,574,400	1,602,467
Total equity / capital	7,886,927	7,902,936
Total liabilities and equity / capital	18,379,456	19,886,767
Boston Properties Limited Partnership [Member]
ASSETS
Real estate, at cost	19,061,141	18,814,558
Less: accumulated depreciation	(3,846,816)	(3,476,321)
Total real estate	15,214,325	15,338,237
Cash and cash equivalents	723,718	1,763,079
Cash held in escrows	73,790	487,321
Investments in securities	20,380	19,459
Tenant and other receivables (net of allowance for doubtful accounts of $1,197 and $1,142, respectively)	97,865	46,595
Accrued rental income (net of allowance of $2,775 and $1,499, respectively)	754,883	691,999
Deferred charges, net	732,837	831,744
Prepaid expenses and other assets	185,118	164,432
Investments in unconsolidated joint ventures	235,224	193,394
Total assets	18,038,140	19,536,260
Liabilities:
Mortgage notes payable	3,438,714	4,309,484
Unsecured senior notes (net of discount of $10,683 and $12,296, respectively)	5,289,317	5,287,704
Unsecured line of credit	0	0
Mezzanine notes payable	308,482	309,796
Outside members’ notes payable	180,000	180,000
Accounts payable and accrued expenses	274,709	243,263
Dividends and distributions payable	327,320	882,472
Accrued interest payable	190,386	163,532
Other liabilities	483,601	502,255
Total liabilities	10,492,529	11,878,506
Noncontrolling interest:
Redeemable interest in property partnership	0	104,692
Redeemable partnership units—0 and 12,667 series four preferred units outstanding at redemption value at December 31, 2015 and December 31, 2014, respectively	0	633
Redeemable partnership units—16,097,473 and 16,453,670 common units and 1,831,714 and 1,496,799 long term incentive units outstanding at redemption value at December 31, 2015 and December 31, 2014, respectively	2,286,689	2,310,046
Preferred stock, $.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, 2015 and December 31, 2014, respectively	193,623	193,623
Boston Properties Limited Partnership partners’ capital—1,715,092 and 1,710,644 general partner units and 151,864,874 and 151,403,301 limited partner units outstanding at December 31, 2015 and December 31, 2014, respectively	3,490,899	3,446,293
Accumulated other comprehensive loss	(18,337)	(12,973)
Noncontrolling interests:
Property partnerships	1,574,400	1,602,467
Total equity / capital	5,258,922	5,242,383
Total liabilities and equity / capital	$ 18,038,140	$ 19,536,260