v2.4.0.8

Real Estate Activity During the Six Months Ended June 30, 2013 (Summary Of The Discontinued Operations Related To Montvale Center, 303 Almaden Blvd and Bedford Business Park) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended			3 Months Ended	6 Months Ended	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Montvale Center and 303 Almaden Blvd [Member] [Member]	Jun. 30, 2012 Montvale Center, 303 Almaden Blvd and Bedford Business Park [Member]	Jun. 30, 2012 Montvale Center, 303 Almaden Blvd and Bedford Business Park [Member]	Jun. 30, 2013 303 Almaden Blvd [Member]	Mar. 31, 2013 303 Almaden Blvd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	$ 515,320	$ 471,349	$ 998,334	$ 915,042	$ 3,376	$ 3,263	$ 7,784	$ 1,529
Expenses
Operating					1,486	1,489	3,392	656
Depreciation and amortization	134,604	111,168	255,199	219,630	596	907	2,310	0
Total expenses	344,505	298,030	697,084	598,156	2,082	2,396	5,702	656
Operating income	170,815	173,319	301,250	316,886	1,294	867	2,082	873
Other expense
Interest expense	(103,140)	(99,901)	(203,573)	(203,138)	(360)	(649)	(1,294)	0
Income from discontinued operations	873	218	934	788	934	218	788	873
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership	(88)	(4,075)	(1,900)	(4,159)	(94)	(23)	(84)	(88)
Income (loss) from discontinued operations attributable to Boston Properties, Inc.	785	33,020	15,975	33,506	840	195	704	785
Gain on sale of real estate from discontinued operations	0	36,877	0	36,877	0	36,877	36,877	0
Gain on forgiveness of debt from discontinued operations	0	0	20,182	0	20,182	0	0	0
Impairment loss from discontinued operations	0	0	3,241	0	3,241	0	0	0	3,200
Noncontrolling interest in gain on the sale of real estate, gain on forgiveness of debt from discontinued operations - common units of the Operating Partnership					1,806	4,052	4,075	0
Gain on Sale of Real Estate, Gain On Forgiveness of Debt and Impairment Losses from Discontinued Operations Attributable to Company					$ 15,135	$ 32,825	$ 32,802	$ 0

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Amount of gain (loss), not previously recognized, resulting from the forgiveness of debt pertaining to a real estate property.

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