Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Preferred Stock [Member]	Additional Paid-In Capital [Member]	Dividends In Excess Of Earnings [Member]	Treasury Stock, At Cost [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interests [Member]
Equity, value at Dec. 31, 2012	$ 5,634,854	$ 1,516		$ 5,222,073	$ (109,985)	$ (2,722)	$ (13,817)	$ 537,789
Equity, shares at Dec. 31, 2012		151,601,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of operating partnership units to Common Stock, shares		929,000
Conversion of operating partnership units to Common Stock, value	0	$ 10		30,281				(30,291)
Conversion of redeemable preferred units to common units	16,494							16,494
Allocated net income for the year	828,757				749,811			78,946
Dividends/distributions declared	(831,826)				(748,378)			(83,448)
Issuance of 5.25% Series B cumulative redeemable preferred stock	193,623		$ 200,000	(6,377)
Shares issued in connection with exchange of exchangeable senior notes, value	43,834	$ 4		43,830
Equity component of exchange of exchangeable senior notes	(43,869)			(43,869)
shares issued in connection with exchange of exchangeable senior notes, shares		419,000
Units issued to Boston Properties, Inc. related to Common Stock issued under the Employee Stock Purchase Plan		6,000
Shares issued pursuant to stock purchase plan, value	681			681
Net activity from stock option and incentive plan, shares		28,000
Net activity from stock option and incentive plan, value	35,571			7,701				27,870
Noncontrolling interest in property partnerships recorded upon consolidation	480,861							480,861
Sale of interest in property partnerships and contributions from noncontrolling interest in property partnerships	687,164			429,600				257,564
Distributions to noncontrolling interests in property partnerships	(5,039)							(5,039)
Amortization of interest rate contracts	2,513						2,261	252
Conversion of redeemable partnership units	0			(21,467)				21,467
Equity, value at Dec. 31, 2013	7,043,618	$ 1,530	200,000	5,662,453	(108,552)	(2,722)	(11,556)	1,302,465
Equity, shares at Dec. 31, 2013		152,983,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of operating partnership units to Common Stock, shares		80,000
Conversion of operating partnership units to Common Stock, value	0	$ 1		2,699				(2,700)
Conversion of redeemable preferred units to common units	33,306							33,306
Allocated net income for the year	513,951				443,611			70,340
Dividends/distributions declared	(1,224,471)				(1,097,523)			(126,948)
Shares issued in connection with exchange of exchangeable senior notes, value	0
Units issued to Boston Properties, Inc. related to Common Stock issued under the Employee Stock Purchase Plan		7,000
Shares issued pursuant to stock purchase plan, value	761			761
Net activity from stock option and incentive plan, shares		44,000
Net activity from stock option and incentive plan, value	27,999			6,822				21,177
Noncontrolling interest in property partnerships recorded upon consolidation	0
Sale of interest in property partnerships and contributions from noncontrolling interest in property partnerships	1,536,382			648,407				887,975
Distributions to noncontrolling interests in property partnerships	(31,118)							(31,118)
Amortization of interest rate contracts	2,508						2,252	256
Conversion of redeemable partnership units	0			(50,885)				50,885
Equity, value at Dec. 31, 2014	$ 7,902,936	$ 1,531	200,000	6,270,257	(762,464)	(2,722)	(9,304)	2,205,638
Equity, shares at Dec. 31, 2014	153,113,945	153,114,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of operating partnership units to Common Stock, shares		424,000
Conversion of operating partnership units to Common Stock, value	$ 0	$ 5		14,338				(14,343)
Allocated net income for the year	794,791				583,106			211,685
Dividends/distributions declared	(671,041)				(601,594)			(69,447)
Shares issued in connection with exchange of exchangeable senior notes, value	0
Units issued to Boston Properties, Inc. related to Common Stock issued under the Employee Stock Purchase Plan		6,000
Shares issued pursuant to stock purchase plan, value	780			780
Net activity from stock option and incentive plan, shares		36,000
Net activity from stock option and incentive plan, value	40,265			5,814				34,451
Acquisition of redeemable noncontrolling interest in property partnership	(1,586)			(1,586)
Sale of an interest in property partnerships	0			(1,053)				1,053
Proceeds from Noncontrolling Interests	2,705							2,705
Noncontrolling interest in property partnerships recorded upon consolidation	0
Distributions to noncontrolling interests in property partnerships	(170,049)							(170,049)
Dissolution of a property partnership	(4,082)							(4,082)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(10,302)						(7,061)	(3,241)
Amortization of interest rate contracts	2,510						2,251	259
Conversion of redeemable partnership units	0			17,137				(17,137)
Equity, value at Dec. 31, 2015	$ 7,886,927	$ 1,536	$ 200,000	$ 6,305,687	$ (780,952)	$ (2,722)	$ (14,114)	$ 2,177,492
Equity, shares at Dec. 31, 2015	153,579,966	153,580,000