Real Estate Activity During The Six Months Ended June 30, 2012 (Summary Of The Discontinued Operations Related To Montvale Center And Bedford Business Park) (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	$ 472,897,000	$ 433,867,000	$ 918,124,000	$ 849,149,000
Expenses
Depreciation and amortization	111,643,000	110,259,000	220,583,000	218,852,000
Total expenses	299,186,000	280,255,000	600,394,000	558,193,000
Operating income	173,711,000	153,612,000	317,730,000	290,956,000
Other expense
Interest expense	99,901,000	94,583,000	203,138,000	193,108,000
Income (loss) from discontinued operations	398,000	(132,000)	884,000	(80,000)
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership	4,094,000	(15,000)	6,115,000	(10,000)
Income (loss) from discontinued operations attributable to Boston Properties, Inc.	33,181,000	(117,000)	49,453,000	(70,000)
Gain on sale of real estate from discontinued operations	36,877,000		36,877,000
Gain on forgiveness of debt from discontinued operations			17,807,000
Montvale Center and Bedford Business Park [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	1,091,000	2,584,000	3,748,000	5,177,000
Expenses
Operating	450,000	1,242,000	1,602,000	2,322,000
Depreciation and amortization	243,000	821,000	1,040,000	1,656,000
Total expenses	693,000	2,063,000	2,642,000	3,978,000
Operating income	398,000	521,000	1,106,000	1,199,000
Other expense
Interest expense		(653,000)	(222,000)	(1,279,000)
Income (loss) from discontinued operations	398,000	(132,000)	884,000	(80,000)
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership	(42,000)	15,000	(94,000)	10,000
Income (loss) from discontinued operations attributable to Boston Properties, Inc.	356,000	(117,000)	790,000	(70,000)
Gain on sale of real estate from discontinued operations	36,877,000		36,877,000
Gain on forgiveness of debt from discontinued operations			17,807,000
Noncontrolling interest in gain on sale of real estate and gain on forgiveness of debt from discontinued operations - common units of the Operating Partnership	(4,052,000)		(6,021,000)
Gain on sale of real estate and gain on forgiveness of debt from discontinued operations attributable to Boston Properties, Inc.	$ 32,825,000		$ 48,663,000